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Nuclear Arms Control: Background and Issues (1985)

Chapter:7 Nuclear Test Bans

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7 Nuclear Test Bans INTRODUCTION The banning of nuclear testing has been a central and continuing objective of arms control since the mid-19SOs. At the end of the Eisen- hower and beginning of the Kennedy administrations, the United States and the United Kingdom made a major effort to negotiate a comprehensive test ban (CTB) treaty with the Soviet Union. Although these trilateral negotiations failed to produce a comprehensive test ban, agreement was finally reached in 1963 on the :Limited Test Ban (LTB) Treaty (Appendix D), which banned all nuclear tests except those con- ducted underground. In 1974 the Nixon Administration negotiated the Threshold Test Ban (TTB) Treaty (Appendix E), which banned under- ground tests above 150 kt; and in 1976 the Ford Administration negoti- ated the companion Peaceful Nuclear Explosions (PNE) Treaty (Appendix F), which provided for the special handling of peaceful explo- sions under the threshold. The Carter Administration renewed the ef- fort to negotiate a comprehensive test ban treaty but failed to produce an agreement. The Reagan Administration has taken the position that, while a comprehensive test ban remains a Tong-term U.S. goal, such a treaty would not be in the security interests of the United States at the present time. BACKGROUND The Eisenhower Administration By the mid-1950s, public opposition to nuclear testing had become a significant domestic and international political force. The recurring 187

188 NUCLEAR ARMS CONTROL U.S. and Soviet nuclear test series, involving growing numbers of explo- sions with rapidly increasing yields, were a constant reminder of th threat and consequences of nuclear war. With the unexpected discovery of the extent of the danger of fallout during the U.S. test series in 1954, nuclear testing was also widely seen as a direct threat to public health and safety. Early proposals to stop testing were opposed within the U.S. government by both military and civilian officials on the grounds that the requirements for more advanced nuclear weapons were so urgent as to far outweigh any immediate health dangers that might be associated with nuclear tests. Questions were also raised about the ability to verify a ban on nuclear tests. In early 1958' following a major Soviet test series, the Soviet Union seized the political initiative by announcing that it would stop testing unilaterally if the United States would do likewise. In a major policy shift in the spring of 195S, President Dwight Eisenhower proposed to Soviet Secretary Nikita Khrushchev that sci- entists from the two sides meet to assess the verifiability of a ban on nuclear tests and to recommend a possible control system. In addition to political concern about the mounting international opposition to test- ing, President Eisenhower's decision reflected the advice of the newly formed President's Science Advisory Committee under James Killian. Challenging the positions of the Department of Defense and the Atomic Energy Commission, the committee advised the President that a test ban could be monitored and would be in the security interests of the United States given the relative status of the nuclear weapons pro- grams of the two sides. The Conference of Experts, which was held in Geneva, Switzerland, during the summer of 195S, brought together a remarkable group of outstanding scientists and specialists on nuclear test detection from the West (the United States, the United Kingdom, France, and Canada) and the East (the Soviet Union, Poland, Czechoslovakia, and Romania). The conference, which was conducted as a technical study and not as a political negotiation, examined the technical problems of monitoring nuclear tests in the atmosphere, in the oceans, and underground. The report of the conference found that an international control system, using available techniques and on-site inspection, would "make it pos- sible to detect and identify nuclear explosions, including Tow-yield ex- plosions (1-5 kt)." The proposed system would have been a worldwide network made up of some 160 to 170 land-based manned control posts and ten ships with appropriate instrumentation. Subsequently, it was agreed in a separate technical working group that the control system could also be applied to tests in space if satellite-borne detectors were incorporated into it.

NUCLEAR TEST BANS 189 On the basis of the findings of the Conference of Experts, President Eisenhower called for formal negotiations on a comprehensive test ban. At the same time he announced a one-year moratorium on all testing provided the Soviet Union did the same. This moratorium was subse- quer~tly extended to the end of 1959 and testing was not resumed until 1961. On October 31, 195S, the United States, the Soviet Union, and the United Kingdom, then the only nuclear powers, opened the Conference on the Discontinuance of Nuclear Tests in Geneva, Switzerland. Despite the technical agreement at the Conference of Experts, the political negotiators quickly found that the sides were far apart in defining how the control system would actually operate and how on-site inspections, which were supposed to resolve questions regarding unidentified events, would be conclucted. The United States and the United Kingdom envisaged a system administered by international personnel and oper- ating by a majority vote, while the Soviet Union insisted on a system that it could control within its own borders. The United States soon complicated the negotiations further by intro- ducing new technical data and new technical problems that brought into question the findings ofthe Conference of Experts. The U.S. delega- tion first reported that analyses of new data from U.S. underground tests conducted after the Conference of Experts indicated that the Tow- est seismic yield that could be iclentified as an earthquake was about twice as high as that originally estimated. More significantly, the U.S. delegation then reported that new studies revealed a number of tech- niques that could permit a violator to conduct relatively large-yield underground tests so that they would not be identified or even detected by the proposed control system. The most striking of the clandestine testing techniques was the con- cept of testing in huge underground cavities. Such cavities were calcu- lated to be capable of decoupling the seismic signal from a nuclear explosion by a factor of 100 or more. The United States also suggested the possibility of conducting tests during very large earthquakes to bury the seismic signal from the test in the much greater signal from the earthquake. The Soviet delegation rejected these technical develop- ments as simply efforts to prevent agreement. In the United States, opponents of the test ban in the executive branch and Congress seized upon the technical developments as conclusive proof that a comprehen- sive ban could not be verified. The U.S. government initiated an exten- sive research and development program (Project Vela) directed at improving seismic monitoring and other verification capabilities. In an attempt to bypass the increasing controversy over the verifica- tion of underground tests, the Eisenhower Administration proposed to ban only those tests that could be verified by the control system devised

190 NUCLEAR ARMS CONTROL by the Conference of Experts. Early in 1960 the United States intro- duced a draft threshold treaty that would have banned all atmospheric and underwater tests, underground tests above magnitude 4.75 on the Richter scale, and tests in space to a distance (unspecified) at which detection was feasible. By defining the threshold in terms of seismic magnitude rather than yield, the proposal sought to avoid the problem of the substantially different coupling factors of explosions in different types of rock and in large cavities. This proposal established criteria that would have called for an estimated average of some 20 on-site inspections per year instead of the open-ended number of~the previous proposal. The United States also proposed that a joint U.S.-Soviet seis- mic research program develop techniques to Tower the threshold. In response, the Soviet Union called for a ban on all space tests, a five-year moratorium on underground tests below magnitude 4.75 while the joint seismic research program was under way, and a political decision on a specific number of on-site inspections. After meeting with British Prime Minister Harold Macmillan, Presi- dent Eisenhower agreed to the concept of a moratorium on tests below the magnitude 4.75 threshold, but only after a threshold treaty with an agreed quota of on-site inspections had been signed and a joint research program agreed upon. (The 1958-59 moratorium was no longer formally in effect, though neither side had conducted any tests since that time.) The Soviet Union accepted this approach, and arrangements were made for a Seismic Research Program Advisory Group to meet in Geneva to develop the joint program. The questions of the length of the morato- rium and the quota of on-site inspections remained. There were also unresolved political problems relating to the organization and opera- tion of the control system. Whatever prospects the threshold approach might have had ended when a U.S. U-2 reconnaissance aircraft was shot down near Sverd- lovsk on May 2, 1960. This led to a crisis in U.S.-Soviet relations and the cancellation of the Paris summit at which it had been planned to seek agreement on the duration of the moratorium and the quota of on-site inspections. The meetings in Geneva on the joint seismic research pro- gram adjourned at the end of May without filing a report when the Soviet delegation indicated there was no point in continuing. The for- mal treaty negotiations in Geneva continued but made no further pro- gress during the remaining months of the Eisenhower Administration. The Kennedy Administration The new Kennedy Administration moved promptly to revive the threshold approach that had appeared to be within reach before the U-2

NUCLEAR TEST BANS 191 incident. On April IS, 1961, after intensive internal reviews, the United States presented a revised draft treaty banning all nuclear tests, including those in space, except for underground tests below mag- nitude 4.75. The treaty was to be coupled with a three-year moratorium on underground tests below magnitude 4.75. The moratorium could be reviewed annually while the joint seismic research program continued. Despite a number of compromises with the Soviet position, the new positions of the United States and United Kingdom and the Soviet Union were still far apart in many respects. The annual quota of on-site inspections became the symbol of these differences. The U.S.~~draft per- mitted 12 to 20 annual inspections in the Soviet Union, depending on the number of unidentified seismic events in the Soviet Union (the same formula would apply independently to events in the United States and the United Kingdom); the Soviet Union would only accept three inspec- tions. There also remained fundamental organizational differences in the two sides' approaches. For example, the United States wanted a single neutral administrator for the control system; the Soviet Union wanted a three-member administrative council (one Soviet, one West- ern, and one neutral member) that could only operate by unanimous consent. The United States wanted the detection stations in each coun- try to be manned by personnel from other countries; the Soviet Union wanted the stations to be manned almost entirely by personnel of the host country. The negotiations were stalemated, and neither side was prepared to make further significant concessions. This phase of the test ban negotiations abruptly ended on August 30, 1961, when the Soviet Union announced its intention to resume nuclear testing, which began the next day. Although there was actually no moratorium in effect at the time, the Soviet action, which came as a complete surprise, generated concern and outrage in official circles and among the public at large. When President Eisenhower had originally proclaimed a one-year moratorium in August 195S, the Soviet Union announced that it would abide by the moratorium as long as the West did. After extending the moratorium through the end of 1959, President Eisenhower, who was concerned that the United States might have to resume testing, terminated the moratorium but stated that the United States would announce any resumption in advance. When the French began testing in February 1960, the Soviet Union denounced the French action as a cover for Western testing. The Soviet Union proceeded to carry out an unprecedentedly inten- sive test series. Within 60 days the Soviet Union conducted 30 atmo- spheric tests, with greater total megatonnage than the total of all previous tests. The series included a gigantic 57-Mt test that was judged in the United States to be a reduced-yield version of the previously

192 NUCLEAR ARMS CONTROL claimed Soviet 100-Mt bomb. As soon as Soviet testing began, President Kennedy ordered the immediate resumption of U.S. testing, and the first test was conducted within two weeks. The initial U.S. tests, which were essentially a political reaction, were conducted underground at small yield. By the spring of 1962 the United States was fully prepared and conducted Operation Dominic, a series of some 40 atmospheric tests in the Pacific that lasted over six months. Among the tests was STAR- FISH, a megaton-yield explosion at an altitude of 400 km that produced unexpected and severe high-altitude effects, including damage to satel- lites at great distances. By the end of Operation Dominic the Soviet Union was engaged in yet another major test series, including a 30-Mt explosion in early August. The cumulative effect of the massive Soviet and U.S. test series was to increase domestic and international concern about both the immediate health effects and Tonger-range military im- plications of what appeared to be a completely unbridled competition in atmospheric nuclear tests. Although the trilateral negotiations on the test ban were adjourned indefinitely in January 1962, world opinion would not permit the nego- tiations to die. Negotiations were resumed in the spring of 1962 in the Eighteen Nation Disarmament Conference (ENDC), the multilateral forum for arms control negotiations. The United States began to relax its verification demands, but this did not narrow the gap with the Soviet position because the Soviet Union hardened its position, proposing a test ban verified only by national means of detection. In the late sum- mer of 1962 the United States ant! the United Kingdom proposed two alternative approaches. One was a treaty banning all nuclear tests without a threshold on underground tests. The provisions of this com- prehensive test ban were essentially those of the previous threshold test ban, although it was suggested that the number of inspections would be reduced. The other approach was a treaty banning tests in or above the atmosphere and in the sea. The Soviet delegation rejected both ap- proaches, the first because it required inspections and the second be- cause it permitted testing to continue. In mid-October 1962 the Cuban missile crisis suddenly brought home to leaders and ordinary citizens everywhere the stark realization that nuclear war could happen. President Kennedy and his advisors were clearly deeply moved by their close involvement in the events. Secre- tary Khrushchev and his advisors also appeared to be sobered by the experience. Following the intense and continuing U.S. and Soviet atmo- spheric test series, the missile crisis intensified world pressure for pro- gress in the nuclear test negotiations, which were then the only serious, well-advanced arms control negotiations in progress. Significantly, the

NUCLEAR TEST BANS 193 UN General Assembly passed two resolutions in the immediate after- math of the Cuban missile crisis, one calling for a cessation of nuclear testing and another calling for either a comprehensive test ban or a limited ban coupled with a moratorium on underground testing. Despite these strong pressures for an early agreement and intensive efforts over the next six months to negotiate formally at the ENDC and informally on a personal basis at various levels, the two sides were unable to resolve the remaining differences in their positions. The quota on inspections remained the major, but not the only, issue. Khrushchev reinstated his earlier offer of two or three annual inspec- tions, reportedly in the mistaken belief that this would be acceptable to the United States. Kennedy eventually agreed to reduce the quota to seven annual inspections. Neither Kennedy nor Khrushchev appar- ently considered themselves sufficiently secure politically to propose a final compromise of five inspections, which appeared to some partici- pants to be a logical outcome of the negotiating process. Kennedy was concerned over the strong opposition to further compromise from the military, the weapons laboratories, and influential members of Con- gress. Khrushchev told Western visitors that he had used up his politi- cal credit with his colleagues by agreeing to permit three inspections. The number of on-site inspections was not the only difference. There was a similar impasse over the number of unmanned automatic seismic stations, or "black boxes," to be located in each country. The United States had accepted the Soviet proposal that these black boxes, which could be safeguarded to ensure the authenticity of their seismic data, should be used in place of manned control posts to eliminate the issue of the nationality of the staff at the posts. The Soviet Union had offered to locate three black boxes in the Soviet Union, and the United States had insisted on eight to ten. The gap was not narrowed. In addition to these quantitative differences that dominated the negotiations on the test ban, the two sides were far from agreement on the so-called modalities governing the conduct of individual on-site inspections and the instalIa- tion and operation of the black boxes. Whether these detailed proce- dural issues, which were critical to the satisfactory operation of the control system whatever the quotas might be, could have been resolved if a political decision had been reached is difficult to judge. Certainly, the United States would have had to back off from the very elaborate inspection procedures it envisaged, and the Soviet Union would have had to grant considerably more access than it had yet shown signs of accepting. The treatment of peaceful nuclear explosions was an issue that had not been resolved within the U.S. government and would eventually

194 NUCLEAR ARMS CONTROL have to be faced with the Soviet Union. Within the Atomic Energy Commission and among influential members of Congress, there was strong support for a program of peaceful nuclear explosions, called Proj- ect Plowshare, for which great economic claims were being made. But it was also recognized within the government that continuation of Project Plowshare was inherently incompatible with a comprehensive test ban. The two sides had earlier tried to finesse the issue by permitting explo- sions for peaceful purposes provided the other side could inspect the internal design of the device to assure that it was not a weapon develop- ment test. Advocates of Project Plowshare, who recognized that such a provision was tantamount to stopping the program since it was most unlikely that either sicle would agree to it in practice, proposed instead that each side be given a quota for peaceful tests or projects. Such a proposal was recognized as being inherently contradictory to the goal of a comprehensive test ban. At the urging of Prime Minister Macmillan, President Kennedy de- cided in the spring of 1963 to attempt to break out of the deadlocked ENDC negotiating framework by sending Averell Harriman to Moscow as a special personal representative to see if some resolution of the test ban issue was possible. In an exchange of personal letters, Khrushchev agreed to receive the Harriman mission. On June 10, 1963, Kennedy announced in his famous American University speech that agreement had been reached to hold high-level discussions in Moscow on the test ban. In the speech, which examined the issues of war and peace and U.S.-Soviet relations in a nuclear world, Kennedy also declared a uni- lateral moratorium on atmospheric nuclear tests for as Tong as other states did likewise. Averell Harriman's instructions were to seek a comprehensive treaty and, if this appeared unattainable, a limited agreement along the lines of the draft treaty the United States had originally submitted to the ENDC the previous year. The impasse on the comprehensive treaty and developments immediately prior to the meeting made it clear that a limited agreement was the hoped-for outcome on both sides. On July 2, Khrushchev announced that the Soviet Union was withdrawing its offer of three on-site inspections, claiming that the West would exploit them for espionage. He also stated that the Soviet Union was prepared to conclude an agreement banning testing in the atmosphere, in outer space, and underwater. The Soviet Union had previously rejected the possibility of such a limited treaty. In the United States there was growing support in Congress for this approach, which the military strongly preferred over a comprehensive test ban. The negotiations began on July 15, and ten days later the Treaty Banning Nuclear Weapons Tests in the Atmosphere, in Outer Space and

NUCLEAR TEST BANS 195 Under Water, or simply the Limited Test Ban Treaty (Appendix D), was initiated. There was essentially no discussion of a comprehensive ban, which was clearly out of reach for quick resolution, and the negotiations proceeded directly to the text of the limited treaty. Both sides clearly wanted an agreement, and the few matters of substance and drafting problems were quickly resolved and cleared directly with President Kennecly and Secretary Khrushchev. The Soviet delegation objected to a proposed U.S. provision permitting atmospheric tests for peaceful purposes if unanimously approved. The U.S. delegation withdrew this proposal when agreement was reached on a provision permitting treaty amendment by a majority of the parties, including the three original nuclear weapon parties, and on a U.S. provision explicitly permitting withdrawal from the treaty. The Limited Test Ban Treaty, which was of unlimited duration, banned nuclear tests in all environments except for underground tests that contained the resulting radioactive debris so that it would not be present outside the territory of the country conducting the test. The treaty was to enter into force when ratified by the United States, the United Kingdom, and the Soviet Union and was open to signature by all countries. The treaty, which was considered verifiable by the National Technical Means (NTM) of the two sides, contained no special verifica- . . . talon provisions. After extensive hearings the Senate advised ratification of the treaty by a vote of 80 to 19. Support for the treaty in the hearings was not universal, with representatives of the weapons laboratories emphasiz- ing the technological limits imposed by confining testing to under- ground shots. An important factor was the support of the Joint Chiefs of Staff, whose position was uncertain until the administration formally agreed to four safeguards that the chiefs proposed. These safeguards involved presidential commitments to conduct a comprehensive and continuing underground test program, to maintain the vitality of the weapons laboratories, to maintain the resources necessary for the prompt resumption of atmospheric testing, and to improve verification capabilities. The treaty was ratified by President Kennedy on October 7, 1963., and entered into force three days later. In general, the treaty was very well received in the United States and throughout the world despite its failure to stop all testing. After the extreme tensions of the Cuban missile crisis, the first major arms con- trol agreement between the United States and the Soviet Union came as a welcome relief. The termination of atmospheric testing also relieved widespread anxiety about immediate health effects. A large number of countries moved promptly to sign the treaty, and others have joined over the years. As of September 1984, 111 countries had signed the treaty

196 NUCLEAR ARMS CONTROL and all but 15 had ratified it. France and the People's Republic of China have not signed the treaty. Initially, both countries continued to test in the atmosphere, but since 1974 France has not conducted any atmo- spheric tests. Although the preamble to the Limited Test Ban Treaty proclaimed the objective of "the discontinuance of all test explosions of nuclear weap- ons for all times," the treaty, by stopping atmospheric testing by the United States and the Soviet Union, had the effect of reducing domestic and international pressure for a comprehensive test ban. As a result, there was little serious effort to achieve a comprehensive test ban until trilateral negotiations were resumed 14 years later in the Carter Ad- ministration. Arms control activities shifted to other fields. During the Johnson Administration the focus of arms control was on the negotiation of the Non-Proliferation Treaty (NPT) (Chapter S). The Non-Proliferation Treaty was inherently discriminatory, since it di- vided the world into nuclear weapon states and non-nuclear weapon states. To balance the commitment of the non-nuclear weapon states not to obtain nuclear weapons or any other nuclear explosive device, the nuclear weapon states agreed to share the benefits of the peaceful uses of atomic energy and to negotiate an end to the nuclear arms race. Article VT ofthe NPT specifically committed all parties to the treaty "to pursue negotiations in good faith on effective measures relating to ces- sation of the nuclear arms race at an early date." Moreover, the pream- ble to the treaty recalled the determination expressed in the preamble of the Limited Test Ban Treaty "to achieve the discontinuance of all test explosions of nuclear weapons for all time and to continue negotiations to this end." In the eyes of most non-nuclear weapon states, nuclear testing, even though it was underground, remained the symbol of a continuing policy of active discrimination uncler the Non-Proliferation Treaty. Many states considered the failure to pursue serious efforts to achieve a com- prehensive test ban to be a violation of the obligation to pursue this agreement "in good faith." This dissatisfaction continued even after the United States and the Soviet Union began the SALT process and achieved significant agreements. At the NPT review conferences in 1975 and 1980, key non-nuclear weapon states strongly criticized the United States and the Soviet Union for failing to make further progress on a comprehensive test ban. The Nixon and Ford Administrations Under President Nixon, arms control focused on the SALT process, which became the centerpiece of his foreign policy with the Soviet Un-

NUCLEAR TEST BANS 197 ion. These negotiations produced the ABM Treaty and the SALT ~ ]:n- terim Agreement in 1972. Although both sides gave little attention initially to the nuclear test ban issue, in the second Nixon Administra- tion interest was suddenly rekindled in the threshold approach to a nuclear test ban. One must review the political situation existing at the time to appreciate this unexpected turn of events. With a summit meet- ing Tong scheduled for mid-1974, both sides shared a common interest in achieving in advance an agreement that would maintain the momen- tum of arms control and the detente process. It was clear that the SALT II Treaty, which was proving more difficult to negotiate than antici- pated, could not be completed by then. As the shadow of the Watergate scandal grew, President Nixon had an additional motivation to demon- strate that he was in control of a dynamic foreign policy. Tn these circum- stances, a threshold treaty with the threshold set sufficiently high to eliminate all verification problems and permit a significant level of testing provided an opportunity for a quick, noncontroversial agree- ment. It bypassed the problem of establishing quotas and procedures for on-site inspections and the persistent opposition of the military and the weapons laboratories to a ban on all testing. The treaty was rapidly negotiated and signed at the summit meeting in Moscow on July 3, 1974. One month later, President Nixon resigned. The Treaty on the Limitation of Underground Nuclear Weapon Tests, or more simply the Threshold Test Ban Treaty (Appendix E), prohibited any underground nuclear weapon test having a yield exceeding 150 kt. At the same time it was agreed that negotiations should continue on a comprehensive test ban. The treaty was a bilateral undertaking be- tween the United States and the Soviet Union and did not even contain provisions for other nuclear weapon states to join. The treaty included a protocol in which the parties agreed to designate the geographic bound- aries of their test areas and to exchange other technical data. These technical data, which were to be made available at the time the instru- ments of ratification were exchanged, included detailed information on the geology of the test sites and data from two calibration shots at each test site. These cooperative measures were designed to assist the other side in translating the seismic magnitude measured by its own seismic monitoring system into an equivalent yield. The seismic signal from an explosion of a given yield depends on both the local and regional geology of a nuclear test site. The two sides were concerned that tests with design yields near the threshold might accidentally produce yields above it, since the weapon laboratories wanted to test as close to the threshold as possible. To cover this contingency a separate understanding was subsequently reached that "one or two slight unintended breaches per year would not be

198 NUCLEAR ARMS CONTROL considered a violation of the treaty" but would be cause for concern and on request would be the subject of consultations. This unusual under- standing was submitted to the Senate as part of the negotiating record. The Threshold Test Ban Treaty was directed specifically at weapon tests and did not deal with peaceful nuclear explosions (PNEs). In the period since the Limited Test Ban Treaty, the Soviet Union had taken over the earlier U.S. enthusiasm for this activity, and at the time of the negotiations it was apparently seriously considering some ambitious earth moving projects to divert rivers from a northern to a southern course. Since nuclear devices really intended for use in nuclear weapons could be tested as part of a legitimate PNE experiment or project, any relaxation of the provisions of the Threshold Test Ban Treaty for PNEs had to be very carefully worked out to maintain the integrity of the treaty. The time pressure of the upcoming summit did not permit this, and it was decided to deal with the PNE problem in a separate compan- ion treaty. The Threshold Test Ban contained a provision obligating the signatories to negotiate such a treaty at "the earliest possible time." After 18 months of intense negotiations, the Treaty on Underground Nuclear Explosions for Peaceful Purposes, or simply the Peaceful Nu- clear Explosions (PNE) Treaty (Appendix F), was signed by Presidents Ford and Brezhnev on May 26, 1976. The treaty extended the threshold of 150 kt on individual nuclear explosions to PNEs but permitted "group explosions" or salvos with yields up to 1.5 Mt. provided that the individual explosions in the salvo did not exceed 150 kt. (Such salvos could be used to excavate large ditches suitable for the Soviet river diversion projects.) The treaty contained an elaborate protocol that spelled out in great technical detail the information that would be ex- changed before any peaceful nuclear explosion. The protocol also pro- vided for detailed on-site observations for salvos whose total yield would exceed the 150-kt threshold. The observers would be allowed to use specified instrumentation to confirm that the yields of the individual shots in the salvo were below the 150-kt threshold. The procedures for making these observations possible were also spelled out in great detail. Reaction within the United States to the Threshold Test Ban and Peaceful Nuclear Explosions treaties was mixed. Supporters argued that they were a significant step toward a comprehensive ban that could be achieved by lowering and finally eliminating the threshold as confi- dence in the agreement was established. They emphasized that the PNE treaty established a sound precedent for serious on-site inspection. The treaties were criticized from different directions. On the one hand, some critics saw the treaties as unnecessarily restricting U.S. testing

NUCLEAR TEST BANS 199 without accomplishing a serious arms control objective. These critics also saw them as being difficult to verify because of the uncertainty in the coupling of yield to seismic signal. On the other hand, some advo- cates of a comprehensive test ban argued that the 150-kt threshold was so high as to be meaningless and that this approach would in fact delay the achievement of a comprehensive ban since the concept of a threshold would be difficult to eliminate once it had been formalized in a treaty. In addition, they argued that institutionalizing PNEs in a formal treaty created yet another barrier to a comprehensive test ban and stimulated interest in this field to the detriment of the Non-Proliferation Treaty. For a variety of political and tactical reasons, the Threshold Test Ban and Peaceful Nuclear Explosions treaties have never been ratified by the United States. Due to the domestic political crisis in mid-1974 and the logical coupling of the two treaties, the Threshold Test Ban Treaty was not submitted for ratification immediately after being signed. By the time the Peaceful Nuclear Explosions Treaty was signed in the spring of 1976, President Ford decided that he did not want to risk a Senate debate in the midst of his political campaign. President Carter did not want to complicate the prospects for ratification of the hoped-for SALT II or CTB treaties for a marginal agreement that both sides were already honoring. During this period both sides made clear at various times their intention not to act inconsistently with these unratified treaties as long as the other side did likewise. The Carter Administration President Carter came into office determined to make rapid progress in arms control, including the achievement of a comprehensive test ban. When Secretary of State Cyrus Vance and Soviet Foreign Minister An- drei Gromyko met in Moscow in March 1977 to establish the arms control agenda for the next four years, it was agreed to resume trilateral negotiations on a comprehensive test ban agreement. The negotiations, which began in the fall of 1977 in Geneva, made significant early pro- gress but slowed as the SALT IT negotiations began to dominate the bureaucratic and political processes in the United States. The domina- tion became complete when the SALT IT ratification process began. Faced with a difficult and uncertain SALT IT ratification debate, the Carter Administration was anxious to avoid reducing the prospects for success by presenting a controversial test ban agreement too soon. The weapons laboratories were strongly opposed to a comprehensive test ban, and senior military officers, whose support was critical to the rati- fication of SALT TI, were known to be concerned about the consequences

200 of a ban, particularly as it might affect confidence in the reliability of an aging stockpile of nuclear weapons. In this atmosphere, difficult policy decisions on the test ban were deferred, and the pace of the trilateral negotiations slowed. Despite the lack of priority afforded the trilateral negotiations, con- siderable progress was made on a draft text for a comprehensive test ban treaty. Although there are differences of opinion as to how close the two sides actually were to final agreement, the overall framework of the approach had been agreed upon and most of the provisions had been drafted. The perennial problems of verification and the peaceful uses of nuclear explosives appeared to have been handled to the general satis- faction of all sides. The form of the agreement was to be a multilateral treaty prohibiting the testing of all nuclear weapons in all environments. The treaty, which would be of short duration, would be open to signature by all countries. A protocol to the treaty established a moratorium on all explosions for peaceful purposes for the duration of the treaty unless an agreed way could be found sooner to preclude the acquisition of military information from the conduct of such tests. The verification problem was to be handled at two levels: international arrangements spelled out in the treaty, and special arrangements among the United States, the United Kingdom, and the Soviet Union. The treaty itself was to be verified by the National Technical Means of the individual signatories, supplemented by an international exchange of seismic data. Any participant could request an on-site inspection to determine whether a suspicious event had been a nuclear explosion. After reviewing the reasons for suspecting the nature of the event, the challenged state would either grant the request or explain why this was not necessary. The treaty also made specific provision for any two or more parties to agree to additional measures to facilitate verification of the treaty. Detailed provisions were developed in the negotiations defin- ing how this would be done in the case of the United States, the United Kingdom, and the Soviet Union. It was agreed that in the case of these parties, National Technical Means would be supplemented by a system of unmanned seismic stations, new versions ofthe oldblack boxes, using agreed-upon high-quaTity seismic equipment with sophisticated en- cryption devices to ensure authenticity of data. It was agreed that ten such stations would be located at specified locations in both the United States and the Soviet Union; the number of stations for the United Kingdom was unresolved. Using data from this system as well as the full resources of their respective National Technical Means, the coun- tries could request inspections that would have to be granted unless NUCLEAR ARMS CONTROL

NUCLEAR TEST BANS 201 explanations were provided. Detailed provisions were agreed upon to govern the rights and procedures to be followed in carrying out invita- tional inspections under the special arrangements involving the United States, the United Kingdom, and the Soviet Union. The perennial issue of on-site inspections was resolved by accepting the Soviet approach of an unlimited number of challenge or invitational inspections, as opposed to the Western approach of a specific quota of mandatory inspections based on seismic events meeting agreed-upon seismic criteria. The United States had concluded that the value of mandatory on-site inspections had been exaggerated, since it was most unlikely that an on-site inspection would ever be allowed in the case of an actual violation. Similarly, an invitational inspection would not be offered in the case of an actual clandestine test. In both cases this denial would have to be taken into account in assessing the probability that an alleged test had actually occurred. By agreeing on a very short (luration for the treaty, reportedly only three years, both sides essentially finessed several underlying prob- lems and differences. This had the effect of deferring but not finally resolving these issues. Thus, continuing Soviet interest in peaceful uses of nuclear explosions was accommodated by a three-year moratorium, after which the subject would have to be reopened. Similarly, the Soviet Union was willing to defer its insistence that China and France join the treaty provided the subject would automatically be reopened after a short period. From the U.S. perspective, the short duration responded to the concern of the military that tests for reliability or other critical purposes might be required after a few years. The process to be followed upon the expiration of the treaty was not agreed upon. The United States wanted to renegotiate and reratify the treaty, while the Soviet Union wanted simply to review and renew the treaty. Within the U.S. government there were differences as to whether the United States should only retain the option to resume testing after the three-year period or actually commit itself in advance to such action. Among the troublesome minor issues that remained was the number of unmanned seismic stations to be located in the United Kingdom. Although the United States and the Soviet Union had each agreed to accept ten such stations, the United Kingdom rejected the Soviet de- mand that it accept an equal number and argued for a much smaller number related to the size of its territory. Both sides considered this a matter of principle and refused to modify their positions. A potentially serious issue that remained to be addressed was the definition of a "nuclear weapons test explosion." This issue, which had always been postponed in earlier attempts at a comprehensive test ban,

202 NUCLEAR ARMS CONTROL is important, since tests of at least some significance for weapons devel- opment can be conducted in the laboratory at yields equivalent to tons or even a few pounds of high explosives. As a further complication, a continuing series of very Tow-yietd nuclear explosions are the basis for the inertial confinement fusion programs that both countries are pursu- ing in the attempt to develop thermonuclear power for peaceful pur- poses. The negotiations did not address the question as to how these Tow-yield military and peaceful experiments, which are far below any verification threshold, would be treated under the treaty. The successful ratification of SALT IT might have generated the politi- cal will to permit rapid resolution of the few remaining issues that divided the two sides. Nevertheless, however these issues might have been resolved, the ratification of a comprehensive test ban treaty would certainly have been strongly opposed by influential groups, including the weapons laboratories and many retired military leaders. With the Soviet invasion of Afghanistan and the suspension of the SALT IT ratifi- cation process, the prospects for agreement evaporated. The trilateral negotiations dragged on through the remainder of the Carter Adminis- tration, but nothing further of significance was accomplished. The ne- gotiations recessed immediately after President Reagan's election and have not resumed. The Reagan Administration Reversing the position of all U.S. administrations since Eisenhower, the Reagan Administration has formally opposed as contrary to U.S. security interests further efforts at this time to achieve a comprehen- sive nuclear test ban. Speaking before the multilateral Committee on Disarmament in Geneva on February 9, 1982, Eugene Rostow, director of the U.S. Arms Control and Disarmament Agency (ACDA), stated that "while a comprehensive ban on nuclear testing remains an ele- ment of the full range of Tong-term U.S. arms control objectives, we do not believe that, under present circumstances, a comprehensive test ban could help reduce the threat of nuclear weapons or to maintain the stability of the nuclear balance." In March 1983, James George, acting director of ACDA, stated in a written response to questions at appropri- ation hearings that the United States requires continued nuclear test- ingfor "the development, modernization, and certification of warheads, the maintenance of stockpile reliability and the evaluation of nuclear weapons effects." Other spokesmen have emphasized the problems with verifying a comprehensive test ban. The Soviet Union has continued to advocate a comprehensive test

NUCLEAR TEST BANS 203 ban. When it became clear that the trilateral negotiations would not be resumed by the Reagan Administration, the Soviet Union presented at the 37th UN General Assembly a document entitled "The Basic Provi- sions of a Treaty on the Complete and General Prohibition of Nuclear- Weapon Tests." This document was essentially an outline of the draft treaty that had been negotiated in the trilateral negotiations during the Carter Administration. The Soviet draft treaty banned all nuclear weapon test explosions in all environments. It was coupled with a coter- minous moratorium on nuclear explosions for peaceful purposes unless an acceptable technique for conducting such peaceful explosions could be found. Verification was by National Technical Means supplemented by the international exchange of seismic data. In the case of suspicious events, any party could request an on-site inspection and would either be granted an "invitational" inspection or be given an explanation. Provision was made for special arrangements, such as those that had been previously worked out at the trilateral negotiations, to be made separately between parties concerning arrangements for on-site inspec- tions. The treaty was to be of unlimited duration once ratified by all permanent members of the UN Security Council, but it could enter into force for a limited period if ratified by only the United States, the United Kingdom, and the Soviet Union. On December 9, 1982, the United States was the only country to vote against a resolution calling for the Committee on Disarmament to con- tinue the consideration of the issues and "to take the necessary steps to initiate substantive negotiations." The vote on this resolution was 111 to 1 with 35 abstentions. The United States continues to refuse to nego- tiate a treaty in the Committee on Disarmament, although it is partici- pating in a committee working group to discuss verification and compliance issues relating to a comprehensive test ban. In the absence of progress on a comprehensive test ban or other arms control treaties, the Reagan Administration came under strong pres- sure from Congress, particularly the Senate Foreign Relations Commit- tee, to proceed with the ratification of the Threshold Test Ban and Peaceful Nuclear Explosions treaties, which had been on the calendar of the Foreign Relations Committee since 1976. In July 1982 it was reported that President Reagan had decided that the two treaties would have to be renegotiated to seek unspecified improvements in their veri- fication measures before they could be ratified. The administration argued that the Soviet Union appeared to be testing over the threshold and that this problem could not be resolved satisfactorily even when the verification provisions in the two treaties were fully implemented upon ratification. When the United States sought to reopen the negotiations

204 NUCLEAR ARMS CONTROL to modify the verification procedures, the Soviet Union refused to rene- gotiate the treaties on the grounds that they were adequate as signed by the heads of state of the two countries. On January 23, 1984, President Reagan declared in a report to Con- gress entitled "Soviet Non-Compliance with Arms Control Agree- ments" that the Soviet Union "is likely to have violated the nuclear testing yield limit of the Threshold Test Ban Treaty." This charge was denied by the Soviet Union and was publicly questioned by a number of U.S. scientific authorities in the field. In September 1984, President Reagan proposed in his speech to the UN General Assembly that the United States and Soviet Union exchange visits of observers to each other's nuclear test sites as a way to resolve questions about the caTibra- tion of the yields of underground tests. Both sides still maintain their intention to continue to observe the threshold in the unratified treaties. In the 1984 presidential campaign, Democratic candidate Walter Mondale attacked the Reagan Administration's repudiation of a com- prehensive test ban and called for prompt negotiation of a treaty as part of his proposed package of arms control measures. To demonstrate the seriousness of the United States in the matter and to facilitate the negotiations, candidate Mondale pledged that upon taking office he would immediately initiate a temporary moratorium on all nuclear weapon tests. The proposed moratorium would last for a fixed period during the negotiations provided the Soviet Union also refrained from testing. THE MAIN ISSUES SURROUNDING A COMPREHENSIVE TEST BAN Overall U.S. Security The specifics of the debate on a comprehensive nuclear test ban have varied over the years, but the underlying issue has been whether such a ban would be in the overall security interest of the United States. The Reagan Administration and other critics of a CTB argue that such a treaty would not be in the U.S. security interest at this time in view of high-priority military requirements that can only be met by continued testing. They assert that these tests are needed to maintain the reliability of nuclear stockpiles, to develop state-of-the-art war- heads for new systems, to develop a new third generation of highly sophisticated weapons for possible application in the Strategic Defense Initiative and other programs, to understand the effects of nuclear ex- plosions on complex weapon systems, and to improve the safety of nu- clear weapons. Critics of a CTB also argue that it would not be ade-

NUCLEAR TEST BANS 205 quately verifiable because the Soviet Union could continue to test cIan- destinely at Tow yields below the threshold of seismic detection and even at higher yields using elaborate concealment techniques. Since they assume the United States would honor the ban while the Soviet Union would not, they assert that the Soviet Union could gradually improve its nuclear weapons capabilities relative to the United States by pre- venting the deterioration of the reliability of its stockpile. Moreover, some critics assert that with such clandestine testing, the Soviet Union might make significant improvements in its nuclear weapons that could affect the strategic balance. Supporters of a CTB argue that achievement of such an agreement would be in the net interest of the United States because it would help slow down the qualitative arms race that threatens strategic stability. Moreover, they emphasize the contribution that such an agreement, which has been the worldwide symbol of progress in arms control for more than 25 years, would make toward creating an international envi- ronment conducive to non-proliferation, since it would eliminate the inherently discriminatory character of the present situation, in which nuclear weapon states continue to test while non-nuclear weapon states are forbidden to do so. These supporters also argue that verification capabilities are now clearly adequate to ensure that clandestine tests could only be conducted at such low yields that they would not contrib- ute to Soviet nuclear weapon capabilities. In response to opponents, these supporters of a CTB assert that such a ban would not endanger the effectiveness of any component of the U.S. strategic deterrent because nuclear testing is not in fact necessary to maintain stockpile reliability. They also assert that new warheads are not necessary for future delivery systems and that a case has not been made for a new or third generation of nuclear weapons except as a component of an accelerated arms race. Similarly, nuclear tests to un- derstand the effects of nuclear explosions are not necessary except as part of a program that would accelerate the arms race. Importance of Testing to U.S. Security The debate over the importance of nuclear testing to national security has shifted over time, as the technology of nuclear weapons matured and the United States lost the substantial technical lead it initially had in the field. Opponents of a CTB have always emphasized the value to U.S. military capabilities of continued testing; supporters of a ban have emphasized the net advantage to the United States of a freeze on both sides' nuclear weapon technology as compared with Soviet and U.S.

206 NUCLEAR ARMS CONTROL gains from continued testing. In the 1960s the technical debate focused primarily on the extension of existing technology to develop a range of strategic and tactical weapons with improved yield-to-weight ratios and to help understand sophisticated weapon effects relating to the anti-ballistic missile programs then under discussion. Opponents of a CTB also emphasized the importance of developing weapons with en- hanced neutron emission for use as antitank and antipersonnel weap- ons in Europe. By the time of the Carter Administration the focus of the debate had shifted to the need for testing to assure the reliability of stockpiled weapons. Today the focus of the debate has expanded from the issue of weapon reliability to include the requirement for a third generation of highly sophisticated weapons. In addition, more emphasis has been placed on requirements for continued tests to determine the effects of nuclear weapons, to develop new state-of-the-art warheads optimized for new weapon systems, and to improve weapon safety. Reliability of Stockpiled Weapons Opponents of a CTB have particularly emphasized the problem of maintaining the reliability of the aging stockpile of nuclear weapons. With the passage oftime, corrosion and other effects of aging can reduce the yield of a weapon or even cause it to fait completely. Reliability is normally monitored by nondestructive checks or by testing without a nuclear detonation. However, CTB opponents from the weapons labora- tories and the military argue that circumstances could arise where these techniques would not reveal the serious impacts of certain aging effects. Thus, a nuclear test would be required to confirm the perfor- mance of an existing weapon or to certify a modification or replacement to correct the problem. Moreover, these opponents point out that these defects, which are not random and may occur after a certain period of time in weapons of a particular design, could over a relatively short period render a significant fraction of one leg of the deterrent force inoperative, since the same type of nuclear weapon is often used on all delivery vehicles of a particular type. Opponents frequently cite two historical incidents to illustrate their point: the malfunction of the Polaris A1 warhead, and a problem relat- ing to the primaries of thermonuclear weapons. The Polaris A1 war- head as originally designed contained a mechanical safety device to prevent a low-order nuclear explosion in case the high-explosive compo- nent was accidentally detonated by fire or shock. After a number of years the safety devices began to jam, so that the weapons would have given a greatly reduced yield if they had actually been fired. Opponents

NUCLEAR TEST BANS 207 recall that modification and replacement of the safety device failed to resolve the problem satisfactorily, and the warhead was eventually replaced with a new improved warhead that required testing. In the case of the thermonuclear primaries, it was discovered through a test that the natural decay of tritium had reduced the yield of the primary (the initiator of the explosion) in a thermonuclear device more than had been calculated and that as a result after a period of time the device failed to operate correctly and gave a greatly reduced yield. Further tests were needed to determine the acceptable shelf life of such weapons. Opponents argue that in both cases nuclear tests were necessary either to resolve the problem or to obtain promptly the most desirable solution to the problem. In the Tong term, opponents argue, the aging of components will inevi- tably require substitution of parts or refabrication ofthe weapons. How- ever, due to changing manufacturing procedures and available materials, slight changes would gradually be introduced into the de- signs over time, gradually reducing confidence in the weapons perfor- mance. In these circumstances, opponents argue, confidence in the reliability and effectiveness of the deterrent force would also gradually decline. Supporters of a CTB argue that, while stockpile reliability is obvi- ously a very important problem, nuclear testing is not required to deal with it satisfactorily. Weapons undergo frequent nondestructive tests to ensure proper operation of all components. If there is a cause for con- cern, the entire weapon except for the active nuclear component can be detonated and sensitive instrumentation can determine whether the physical conditions necessary to initiate a nuclear detonation had been created. It is asserted that this type of quality control will identify any deterioration in materials or components or any malfunction in the operation of the weapon. If problems are discovered, components can be replaced or, if necessary, the entire weapon can be refabricated accord- ing to the precise specifications that were originally judged satisfactory for the certification of the weapon's reliability. Historically, nuclear testing has been used very rarely to resolve reli- ability problems in proven designs, supporters of a CTB point out. In the few cases where nuclear tests were conducted for reliability purposes, they were not in fact necessary to ensure reliability of the weapons but allowed a quick or optimized resolution of the problem. With regard to the Polaris A1 warhead, supporters observe that the mechanical prob- lem could have been solved by enforcing production standards and peri- odic replacement. The need for testing arose when a new design that was inherently safe and did not require a safety device was substituted

208 NUCLEAR ARMS CONTROL to eliminate the source of the problem. With regard to the problem of thermonuclear primaries, supporters point out that this unique situa- tion arose from the fact that the primaries contained tritium, which decays relatively rapidly (it has a 12-year half-life). This decay leads to a reduced concentration of tritium, a critical component in the weapon design. When a question of shelf life arose because of this well-known tritium decay, it could always have been resolved conservatively at some cost and inconvenience by maintaining a reasonably fresh supply of tritium in the warheads. In any event, supporters argue, this unique situation of rapid and predictable aging is now understood and compen- sated for, and there is no reason to think a comparable situation will arise with existing weapons. Looking 20 or 30 years into the future, supporters assert that stockpiled weapons can be periodically refabrica- ted according to original specifications on a carefully preplanned sched- uTe. If any genuine concerns exist as to the inability of obtaining identical materials or components in the future, this problem can be solved by Tong-range planning of procurement and stockpiling. Supporters of a CTB also point out that the reliability currently re- quired of nuclear weapons far exceeds the reliability of delivery sys- tems. The nuclear component of a weapon system is expected to have almost perfect reliability, while the reliability of a major missile system is often estimated in the 80 to 90 percent range. Supporters also point out that the hypothetical problem of having all the warheads on one leg of the strategic triad become inoperable due to a common failure would be eliminated by having some mix of existing warheads on each major delivery system. Some supporters of a CTB would acknowledge that after a generation without any nuclear testing, political and military leaders might well have less personal confidence in the stockpile regardless of its intrinsic reliability. They argue, however, that this would in fact be a stabilizing factor, since a preemptive counterforce strike demands the highest con- fidence in the reliability of the strike force while the deterrent value of the retaliatory force will always remain even if there is some putative uncertainty as to the reliability of individual weapons, or even types of weapons. Moreover, the deterrent value of the U.S. retaliatory force would be reinforced by the fact that an adversary could not possibly have detailed information on the reliability of U.S. nuclear weapons and would have to assume that they would function as designed. Development of New Weapons Opponents of a CTB argue that future weapon systems will require specially designed nuclear warheads that will have to be tested even if

NUCLEAR TEST BANS 209 the warheads use state-of-the-art technology. These new warheads will be necessary to optimize the effectiveness of the particular delivery system, they point out, since existing warheads were designed to opti- mize other systems. New or modified designs will also be necessary to meet specific physical constraints of new systems, such as weight, vol- ume, center of gravity, or ability to withstand high accelerations. Con- sequently, the use of existing warheads could significantly reduce the potential effectiveness offuture delivery systems. In some cases, the use of existing warheads may not even be technically possible. Opponents also argue that nuclear weapons technology is far from being mature and that a new or third generation of nuclear weapons could be of tremendous military significance. They foresee nuclear weapons that would use special effects to extend the power of nuclear explosions to great distances. In connection with President Reagan's Strategic Defense Initiative, some opponents of the CTB have focused particular attention on the potential of an X-ray laser, pumped by the explosion of a thermonuclear weapon, as a kill mechanism against at- tacking ICBM boosters and RV busses. In this concept, the X-ray radia- tion from an exploding thermonuclear weapon would power an external laser device that could project a narrow cone of intense soft X-ray radia- tion to distances of thousands of kilometers in space. Other exotic appli- cations that use nuclear explosions as a source of power in space are also under consideration as part of the Strategic Defense Initiative. These opponents argue that a CTB would clearly preclude these and other undiscovered concepts that could prove to be critical components of a truly effective ballistic missile defense system. They maintain that these new concepts illustrate the potential of further nuclear testing to contribute to the security of the United States in fundamental and revolutionary ways. Supporters of a CTB agree that it would indeed impede the continued qualitative improvement of nuclear delivery systems and would pre- vent some developments entirely. But they argue that this is precisely why a CTB is relevant to controlling the U.S.-Soviet arms race. More- over, the constraints imposed by a test ban would tend to stabilize the strategic positions of the two sides, since they would discourage the optimization of counterforce systems without altering the inherent de- terrent capabilities of current or future retaliatory forces. With regard to the specific problem of providing warheads for planned or foreseeable delivery systems, supporters point out that for better or worse these systems could use existing tested designs without signifi- cantly changing the basic missions involved. This might involve some adjustments in asserted requirements or even in system design to ac- commodate existing warheads. In the past, they point out, require-

210 NUCLEAR ARMS CONTROL meets were stated and systems optimized on the premise that warheads could be treated by the military as a free good, separately funded and ordered to specification. In the future, assuming that the arms control regime permitted new systems, the availability of acceptable warheads would have to be treated as one of the fixed parameters of the system. Supporters argue that this inconvenience would discourage unneces- sary improvements but would not prevent any high-priority develop- ments that were really needed to protect the survivability of the deterrent. Supporters also argue that most deterrent systems could now be diversified by equipping them with more than one type of nuclear weapon. Thus, in the unlikely case that a defect would remain uncor- rected, only a fraction of that delivery system would be affected. Finally, these supporters argue that a CTB would make a major con- tribution to stopping the arms race by effectively blocking a third gener- ation of radically new nuclear weapons, since such weapons would clearly require extensive and prolonged testing. Although some ofthese supporters of the CTB strongly question the technical status, practical prospects, and military significance of the concepts advanced so far, they emphasize that the initiation of such a program with grandiose claims would open a major new front in the nuclear arms race. Conse- quently, the ability of a CTB to contain this development, according to supporters, again illustrates its importance to containing a U.S.-Soviet arms race in space. Moreover, attempts to develop such systems, whether successful or not, would lead not only to the termination of the SALT ~ ABM Treaty but to the abrogation of the Limited Test Ban Treaty as well, since such applications would eventually require testing in space. In short, supporters of a CTB argue that it would preclude a range of weapons developments that could contribute to the acceleration of the nuclear arms race without precluding future weapons systems that might contribute to the survivability of the deterrent. Nuclear Effects Opponents of a CTB argue that there is an important military require- ment for better understanding of the effects of nuclear explosions on various critical U.S. military systems. Although a great deal of experi- mental data and calculations exist on this subject, opponents point out that it can be extremely difficult to assess the ability of particular components or overall systems to function in a nuclear environment without actual experiments. Components such as transistor circuits, sensors, or guidance systems can be affected in ways that would cause

NUCLEAR TEST BANS 211 an entire system to malfunction. For this reason, they argue, tests of nuclear effects must be continued to protect the reliability of the deter- rent force. Some opponents of a CTB go further and emphasize the potentially critical importance of the complex electromagnetic effects of nuclear explosions in space on the atmosphere and on systems in space and on earth. These effects could have a major impact on communications, on radars, and on any satellite systems in space. Until these effects are better understood, opponents argue, there will be serious questions about the survivability of the command and control system for the strategic forces on which deterrence depends. Opponents also empha- size that knowledge of these effects may play a critical role in develop- ing an effective ballistic missile defense system. On the one hand, it may be possible to exploit such effects to the advantage of the defense. On the other hand, if not understood and successfully countered, these effects could cause the complete collapse of the system, because radars, other space- and ground-based sensors, and communications on which the system depended could fait catastrophically in a nuclear environ- ment even though they were not directly attacked. This argument brings into question the Limited Test Ban Treaty, since such tests would generally have to be conducted in space. Some opponents of a CTB also emphasize the need for full-scare tests to determine the actual hardness of missile silos to blast and other effects in order to assess the survivability ofthe land-based TCBM force. This argument again brings into question the Limited Test Ban and the Threshold Test Ban treaties, which would ban most tests of this type. Supporters of a CTB agree that it would limit the information on nuclear effects that could be obtained and reinforce the already severe constraints on assessing the potential effects of high-altitude explosions imposed by the Limited Test Ban Treaty. However, they point out that the tests permitted under the Limited Test Ban would add little addi- tional useful effects information that cannot be calculated or deter- mined by nonnuclear sources, such as X-ray generators, particle accelerators, high-explosive impulses to simulate X-ray shock, and other. techniques. They assert that this nonnuclear approach would provide sufficient information to assess the vulnerability of existing warheads and delivery systems to nuclear radiation and to ensure ade- quate communications to release retaliatory strategic forces. Supporters of a CTB argue that the limitations on high-altitude tests significantly constrain the development of ballistic missile defense sys- tems, which they believe are essentially destabilizing and a major stim- ulant to the nuclear arms race. As long as these high-altitude effects are

212 NUCLEAR ARMS CONTROL very uncertain, they argue, it would be difficult to justify proceeding with a ballistic missile defense system in which little confidence could be placed. Even though some supporters are confident that more infor- mation on this subject would not improve the prospects for an effective defense system, they argue that pursuit of such a test program would prove a provocative stimulant to the arms race. Each side would fear that the other side had developed new information that might make its defense system more effective. With regard to the determination of the precise hardness of missile silos to overpressure and other nuclear effects, supporters argue that this is not a critical issue in the survivability of the U.S. strategic deterrent. Moreover, full-scare atmospheric tests or even underground tests with very large yields, which would be required to advance sub- stantially the current state of knowledge, are already banned by the Limited Test Ban and Threshold Test Ban treaties. The underground tests permitted under the Threshold Test Ban would not yield signifi- cant data that could not be obtained by sophisticated high-explosive tests of the type already conducted by the United States, according to supporters. In any event, the exact level of hardening is not a critical factor in assessing the credibility of the deterrent, since the extremely high missile accuracies that have already been achieved and the fur- ther improvements that can be expected will make all silos vulnerable to attack. Moreover, with the demise of the "dense pack" concept of MX deployment, there is no current need for superhardening of silos. Finally, supporters emphasize that while some tests of nuclear effects on components can be carried out in the laboratory, a CTB has an equal impact on such tests for both the United States and the Soviet Union. Safety Some opponents of a CTB argue that it would interfere with efforts to improve the safety of nuclear weapons in the event of an accident in- volving nuclear weapons. Although such an accident or terrorist attack would not produce a nuclear explosion, it could cause the high-explosive component of a nuclear weapon to go off, dispersing several kilograms of dangerously radioactive plutonium in the general vicinity. Such acci- dents can present a local health problem with potentially serious politi- cal implications. There have been several such accidents, including one at Palomares, Spain, where a bomber loaded with nuclear weapons crashed and contaminated a small community. Opponents point out that this problem can be eliminated by substituting special insensitive high-explosive components that will not detonate from the shocks and

NUCLEAR TEST BANS 213 heat experienced in accidents or terrorist attacks. The substitution of the new insensitive high explosives will require retesting of the im- proved weapons, since differences in the burning characteristics of these high explosives require minor modifications in design. Supporters of a CTB argue that, while improved safety is certainly desirable, the dispersal of plutonium is a relatively minor problem com- pared with the contribution a CTB would make to controlling nuclear weapons. Moreover, they observe that this problem has been recognized for some time and that any modifications that have not already been made couicl be incorporated and tested before a ban on nuclear weapon tests entered into effect. Peaceful Nuclear Explosions Some opponents of a CTB argue that such a ban would preclude the development and use of peaceful nuclear explosives, which they claim hold great economic promise. This was a major issue during the 1960s, when the U.S. weapons laboratories were widely prociair~ing the tre- mendous contributions PNEs wouIcI make in such diverse fields as gas and of] production, mining, electric power generation, and large-scale earth moving. Earth moving on a grand scale appeared the most imme- diate and dramatic application, and serious study was given to such proposals as constructing an alternate sea level canal to the Panama Canal and creating a new harbor in Australia. A major development effort, Project Plowshare, was undertaken to explore these applications. But with a more realistic assessment of the technical and political prob- lems associated with these projects as well as their economic prospects, the early enthusiasm in the United States for PNEs waned. By the 1970s the Soviet Union had become the principal advocate of PNEs. It expressed serious interest in large earth moving projects to (livers rivers so that they would flow south to the Caspian Sea instead of north into the Arctic Ocean, and a number of tests of various other applications were conducted. As a consequence of this interest, the So- viet Union, in the trilateral negotiations during the Carter Administra- tion and in its recent treaty outline, called for a ban on all military nuclear explosions but only a moratorium on PNEs until a satisfactory method could be found for preventing such activities from being used for military purposes. It is not clear whether the Soviet move was simply an effort to finesse internal pressure for PNEs or a serious effort to hold open a PNE option. Supporters of a CTB generally agree that such a treaty would prevent further progress in PNEs, since it does not appear possible as a practical

214 NUCLEAR ARMS CONTROL matter to distinguish PNE developments from activities of potential military significance. (A few supporters of a CTB suggest that a mutu- ally satisfactory technique for continuing PNE activities might be de- veloped in the future.) All supporters of a CTB contend that PNEs are not sufficiently important to economic development to be allowed to interfere with a CTB treaty that would contribute significantly to the prospects for peace. Moreover, many supporters challenge the economic claims of PNE advocates. They also argue that many PNE applications, such as major earth moving projects, would be politically unacceptable in today's world because of the associated nuclear fallout and other effects, such as blast and earth shock. Finally, supporters of a CTB point out that efforts to accommodate a future PNE option in a CTB treaty undercut the non-proliferation value of the treaty. Some potential nuclear weapon states seized on advocacy of PNEs by the United States during the 1960s as a reason for seeking an independent capability to produce nuclear explosives. For example, the Indian government claimed that its first nuclear explosion in 1974 was actually part of a PNE program. With this history in mind, sup- porters of a CTB argue that continued efforts on the part of the nuclear powers to retain a PNE option will provide potential nuclear weapon states with a rationale for keeping open a nuclear explosives option on the grounds that it might be needed for a PNE program. The Weapons Laboratories Opponents of a CTB argue that such an agreement would seriously weaken U.S. weapons laboratories without having a comparable effect on Soviet laboratories. They assert that the agreement would deny U.S. weapons designers the opportunity to test their ideas and products. As a result, morale at the weapons laboratories would suffer, gifted weapons designers would leave, and new ones could not be recruited or trained. This would seriously impair the ability to resume vigorous weapons programs in case the agreement ended. While granting that such fac- tors would to some extent also affect Soviet laboratories, opponents assert that the Soviet Union would find ways to ensure that key person- nel remain at the weapons laboratories and continue to make signifi- cant contributions. Moreover, the potential for cheating through low-yield clandestine tests could give Soviet laboratories much greater opportunities to test new ideas and maintain a vigorous research and development program. Some opponents of a CTB argue that leaclership in nuclear weapon developments has been a major element in U.S. military strength, offsetting other Soviet military advantages, and that

NUCLEAR TEST BANS 215 any weakening of the weapons laboratories undermines the source of this U.S. technological advantage. Supporters of a CTB argue that it is the purpose of the treaty to slow down to the extent possible all nuclear weapon developments. On bal- ance, they assert that it is not obvious that Soviet weapons laboratories would have a significant advantage in such an environment. While weapons research would clearly be curtailed, U.S. laboratories have a major advantage in their greatly superior computational equipment and their extensive experience with simulated nonnuclear effects tests. Moreover, in contrast to the Soviet laboratories, the two U.S. weapons laboratories have highly diversified research programs, with roughly one half of their present activities outside the nuclear weapons area. In addition, many of the technical and analytical problems in the peaceful inertial confinement fusion programs of the two laboratories overlap problems encountered in weapons design. Such programs should help maintain the skills of weapons designers while engaging them in inter- esting and important work. Finally, scientific productivity cannot be coerced, supporters of a CTB argue, even though the Soviet Union may be able to inhibit the departure of key scientific personnel. Verification General Verification has been a central issue in the CTB debate since the mid- 1950s. The underlying question has been, What would be the military significance of testing that could be conducted clandestinely beneath the threshold of the monitoring system? Most CTB opponents have argued that activities of military significance could be clandestinely conducted by the Soviet Union under a CTB. In contrast, most CTB supporters have argued that there would be adequate verification to ensure that the Soviet Union or other countries were not conducting nuclear tests that could have any real military significance. Nuclear explosions are unique events. The large amount of energy and forms of radiation they generate produce a variety of physical phe- nomena that can be detected at great distances. From the beginning the debate on verification focused primarily on underground tests, since tests in the atmosphere, oceans, and space appeared to be adequately verifiable. Early tests were all in the atmosphere, and by the late 1940s techniques were developed to detect even Tow-yield tests by their acous- tic signals and unique radioactive debris. Today these tests can be moni- tored very effectively from satellites through the visible and near-

216 NUCLEAR ARMS CONTROL infrared light emitted from the explosion. Underwater nuclear ex- plosions can be monitored to very Tow yields, far below the threshold of underground tests, by existing acoustic sensors associated with anti- submarine warfare systems. Nuclear explosions in space at vast dis- tances can be monitored from satellites by their characteristic X-ray . . emissions. Underground tests present a more serious technical challenge. The seismic signals they produce must be not only detected but distin- guished from a large background of seismic signals from natural earth- quakes whose numbers rapidly increase at lower magnitudes. The identification process benefits from the fact that the seismic signals of explosions differ in a number of significant ways from those of earth- quakes. Explosions are a point source of energy in space and time, while earthquakes result from the slipping of faults over a considerable dis- tance. Over the last 25 years there has been a major effort to understand this problem and to improve the capabilities to monitor underground tests. A number of seismic techniques that were available from the begin- ning of the debate have been refined. These include seismic determina- tion of the location and depth of the event and the "first motion" of the initial compression wave transmitted through the earth. Over the years a number of additional techniques have been developed that depend on the differing spectrums of the seismic signals from explosions and earthquakes. Specific criteria are sometimes difficult to formulate, but many seismologists believe that the overall spectrum and complexity of seismic signals clearly differentiate the two types of events. Experts, including those opposed to a test ban, generally agree that these collective criteria can separate explosions from earthquakes and identify suspicious events, but assessments of the threshold of identifi- cation and level of confidence differ. Location can normally be deter- mined with confidence to within 25 km. Depths can be determined to within 15 km, which is greater than current drilling capabilities. Most earthquakes (more than 90 percent) are either located in the deep ocean or more than 30 km underground, which automatically eliminates them from concern. Of the earthquakes in the Soviet Union and its coastal waters, 75 percent are in or near the Kamchatka Peninsula and the Kurile Islands and tend to have very deep focuses and to be offshore. With these events eliminated, an estimated average of around 100 earthquakes per year occur in the Soviet Union with body wave magni- tudes greater than 3.S on the Richter scale (equivalent to less than a 1-kt explosion in hard rock). Originally it was proposed to identify these residual earthquakes by

NUCLEAR TEST BANS 217 the so-called first-motion criteria. An explosion sends an initial com- pression wave through the earth in all directions, since it compresses the surrounding medium symmetrically. An earthquake, which is gen- erated by a sTipfault, sends initial compression waves in some directions and rarefactions in others. This provides a very powerful technique for differentiation provided there are enough stations in the monitoring system and the signal is sufficiently strong to be recorded with confidence. The discriminants that compare various segments ofthe seismic spec- trum take advantage of the fact that earthquakes put a substantially larger fraction of their energy into modes other than compression waves because of the complex nature of their sources. In exploiting this well- established phenomenon, particular attention has been given to com- paring the magnitudes of a given event as measured by surface waves and by body waves. An explosion with the same body wave magnitude as an earthquake has a much smaller surface wave magnitude, since much less of its energy goes into surface waves. This same general phenomenon leads to a number of more qualitative criteria that are very persuasive to most seismologists. The coupling of energy from a nuclear explosion to its surroundings creates another problem. The seismic monitoring system measures the seismic magnitude, not the yield, of an explosion. The yield equivalent to a seismic signal must be estimated by calibration shots or caTcula- tions. The coupling factor depends not only on the immediate medium in which the explosion occurs but also on the general geologic location of the event. In general, equivalent yields are referred to hard rock, which gives the best coupling of energy between an explosion and the sur- rounding medium. The poorest coupling occurs in deep dry alluvium deposits, which may have a coupling factor only one-tenth that of hard rock. If a nuclear test occurs in a sufficiently large cavity that does not collapse during the explosion, it is theoretically possible to reduce the coupling by a factor of as much as 100. In addition, there are regional biases in the coupling of seismic signals. For example, most seismolo- gists believe that seismic body waves from the shots at the U.S. test site in Nevada, where the United States obtains its calibration data to re- late magnitude and yield, are by virtue of the regional geology less well coupled than are Soviet explosions in the Semipalatinsk test area. If correct, this would cause a systematic overestimation of the test yields at Semipalatinsk. However, in the absence of reliable calibration data, the precise magnitude of such an effect remains uncertain. By visiting the site of a suspicious seismic event, it is possible to obtain direct or indirect physical evidence of a nuclear explosion. From

218 NUCLEAR ARMS CONTROL seismic data alone the location of the event is uncertain to within 10 to 25 km. However, information from other National Technical Means may focus attention on a specific location because of surface collapse, scarring, or evidence of unusual human activity. On the ground, investi- gators might find telltale traces of escaping radioactive gases or circum- stantial evidence of surface fracturing or human activity that would lead to further efforts to obtain definitive samples of radioactive debris. Threshold of Detection and Identification Opponents of a CTB argue that tests with significant yields could be tested under that threshold of identification or even the threshold of detection. Even without sophisticated evasion techniques, according to some opponents, the Soviet Union could be confident of successfully conducting explosions with yields in the 10- to 20-kt range by testing in dry alluvium, a light sandy material. They point out that thresholds of a kiloton or so assume hard rock coupling. Some opponents also argue that by firing shots in large underground cavities, the Soviet Union could clandestinely conduct tests with yields up to 100 kt. Supporters of a CTB argue that the system that the Soviet Union appeared to be prepared to accept would have an effective threshold of identification of around 1 kt. They assert that in hard rock the threshold would actually be less than 1 kt. While agreeing that equivalent yields would be greater in other media, they assert that the extreme case of dry alluvium is misreading since this material does not exist in the Soviet Union at depths necessary for clandestine testing above a kiloton. Moreover, they point out that even when fully contained, shots in allu- vium and other media that couple less well than hard rock at the Ne- vada test site leave distinctive subsidence craters that can easily be identified from the air. By properly distributing 10 or 15 unmanned seismic stations within the Soviet Union, according to supporters, the threshold of identification for explosions in any medium, including allu- vium, would be a kiloton or less. Supporters of a CTB argue that the threat of evasion posed by "big hole" decoupling has been greatly exaggerated by opponents of a CTB treaty. They point out that the cavity required to decouple a 100-kt shot would have to be 150 m in diameter at a depth 2 km below the surface, an unprecedented engineering project in hard rock. A more practical approach would be to create a cavity in a salt dome by solution mining, although such cavities would be restricted to much smaller sizes. How- ever, these supporters assert that the only suitable salt domes in the Soviet Union are located in the Caspian Sea area and could be specially monitored by a few properly located unmanned seismic stations. These

NUCLEAR TEST BANS 219 stations, which because of their location could record close-in seismic signals, would be extremely effective since any seismic disturbance in this aseismic area would be a suspicious event. With such a monitoring system, some of these supporters argue, clandestine tests could not as a practical matter be successfully concealed in these salt domes at yields much above a kiloton. Hiding in Earthquakes Some opponents of a CTB contend that it would be possible to test clandestinely by carrying out the test during a major earthquake so that the seismic signal from the explosion would be lost in the earth- quake's extended seismic disturbance. They assert that it would be possible to design a test so that a device with a yield far above the threshold of the monitoring system could be held in readiness for an extended period and fired at the proper moment to avoid separate detection. Supporters of a CTB dismiss this as a serious clandestine testing technique. A test program conducted by holding devices in readiness for months or years to be fired on one or two minutes notice after the initial detection of an entirely unpredictable event is not credible, they main- tain. Moreover, in the very unlikely event that such a clandestine test were attempted, it would be extremely difficult to hide from the pro- posed monitoring system if it were significantly above the threshold. Supporters point out that it would be virtually impossible for the Soviet Union to conduct such a test near the origin of a large earthquake. The only area of the Soviet Union that has such earthquakes with reason- able frequency is the Kamchatka Peninsula and Kurile Islands region, where seismic events can be carefully monitored by nearby seismic equipment in Japan and Alaska, by very sensitive underwater seismic arrays, and by any unmanned seismic stations located in the immediate area as part ofthe monitoring system in the Soviet Union. Since the test would have to be hidden in the signal from a distant earthquake, it would be very difficult to match the exact timing and magnitude of the test with the arriving earthquake signal. Even if this extremely diffi- cult task were successfully accomplished, supporters assert, there is a good chance that the test would still be identified as a separate, and therefore very suspicious, event. Nonseismic Information Some opponents of a CTB argue that nonseismic sources of informa- tion cannot be counted on to help verify compliance. They point out that

220 NUCLEAR ARMS CONTROL if the Soviet Union attempted to evade the agreement, it would be extremely careful to avoid obvious activities that might arouse suspi- cion in advance or help identify a test after the fact. Supporters of a CTB argue that nonseismic sources of information would contribute significantly to verification capabilities. Satellite photography would contribute in many ways to determining whether an unidentified seismic event was in an area of other suspicious act~vi- ties. Such reconnaissance could narrow, or even pinpoint, areas of con- cern for an on-site inspection. For example, efforts to construct a big hole for decoupling purposes or the subsidence crater from a shot in alluvium or other media would be easily identified by such observa- tions. These supporters emphasize that the deterrent value of the entire intelligence operation should not be underestimated since the Soviet Union could not be certain that information suggesting the evasion of a test ban would not come to the attention of U.S. or allied intelligence from technical or human sources. On-Site Inspection Opponents of a CTB tend to argue that the right to a substantial number of on-site inspections is essential to a verifiable agreement. Some opponents take the position that this is the only way to prove a violation. Others assert that individual on-site inspections would be so ineffective that even substantial numbers would have little chance of discovering a clandestine test program. The seismic monitoring system would only locate an event to within 10 to 25 km, they point out, and a deeply buried shot would produce little, if any, surface disturbance. Opponents argue that on-site inspections must be mandatory to b useful. Invitational inspections of the type envisaged in the trilateral negotiations during the Carter Administration would be of little or no value, they assert. It is unrealistic to imagine that a country would invite an inspection if there had actually been a test unless it was certain that the test could not be discovered. Supporters of a CTB argue that on-site inspections, even if they re- quire an invitation after a challenge, are a useful deterrent to ciandes- tine testing. However, they disagree that an on-site inspection is needed to make the case that a nuclear test has in fact occurred since seismic criteria are capable of identifying most explosions as explosions above the threshold with high confidence. White agreeing that an invitation would be unlikely in the case of an actual test, these supporters argue that if serious suspicions existed, the denial of an invitation without a very persuasive explanation would indicate that a violation had in fact

NUCLEAR TEST BANS 221 occurred. Consequently, there would be a strong motivation to grant an invitational inspection to clear the record if, in fact, there had not been a clandestine test. Supporters contend that individual inspections could be very effective in resolving specific suspicious events. While seismic means alone could only locate the event to within 10 to 25 km, satellite reconnaissance could identify surface subsidence or suspicious human activities that couIc3 focus the inspection process. During the inspection, the presence or absence of traces of unique radioactive gas and of characteristic surface disturbances could adequately resolve suspicious cases. Significance of Testing Below the Threshold Opponents of a CTB argue that even below a kiloton the threshold claimed by many CTB supporters important weapons work could still continue on tactical weapons, weapons effects, and the physics of weap- ons design. They also contend that at a threshold of 10 to 20 kt, which many opponents believe is a more realistic estimate, it would also be possible to carry out some important reliability tests that could help maintain confidence in the stockpile. Opponents would also argue that if the threshold can be pushed up to 25 to 100 kt with big hole decoupling or by hiding tests in earthquakes, it would be possible to make major developments in certain types of nuclear weapons and test the reliabil- ity of any nuclear weapon regardless of its design yield. In this connec- tion, some opponents would note that, while a major development program would require many tests, only a few tests would be required to maintain confidence in stockpile reliability. Opponents also emphasize the importance of any of these test programs to sustaining the effective- ness and responsiveness of Soviet weapons laboratories. In this way, the Soviet Union could have an option to resume testing openly with an asymmetric advantage. Supporters of a CTB argue that clandestine testing below a kiloton or even several kilotons would not contribute to existing Soviet weapons capabilities. It would also not give the Soviet Union an asymmetric advantage in reliability testing, they continue, since the operation of most warheads, including all of those on strategic systems, could not be confirmed at these low yields. Moreover, supporters question whether such testing would give the Soviet laboratories any real advantage in maintaining interest and morale, since U.S. laboratories would have opportunities to continue work with computers and simulated nonnu- clear effects and to carry out related peaceful research activities. Sup- porters dismiss as unrealistic the possibility that testing at yields much

222 NUCLEAR ARMS CONTROL above a few kilotons could be carried out and note that many tests would be required to conduct a sustained weapons development program. Con- sequently, these supporters conclude that a clandestine program would not have any effect on the military balance. Significance of Very Low Yield Tests Some opponents of a CTB argue that nuclear tests of military interest can be conducted at such low yields, a few tons or less, that there is no possibili by of detection. They assert that these experiments, which can be condo Acted at a laboratory, are useful in studying the physics of nu- clear em '1osions, in advancing safety, and in maintaining laboratory competence and interest. They also point out that, if taken literally, a complete ban on all nuclear explosions would also ban the peaceful inertial confinement fusion program, which involves a continuous pro- cess of tiny explosions and possibly other approaches to controlled ther- monuclear power as well. It is a fundamental error, they contend, to include in a ban a category of activities that is clearly unverifiable. Supporters of a CTB argue that this is not a real problem affecting U.S. security interests since these tests would not significantly advance either side's nuclear weapons program. The problem can be handled either by a formal definition of nuclear explosions at a very Tow level or by an unstated de minimis interpretation that would effectively ex- clude very Tow level laboratory activities from the ban. Supporters add that the history ofthe CTB negotiations makes it clear that neither side had any intention of banning the inertial confinement fusion program or other efforts to develop fusion or fission reactors. Impact on Nuclear Proliferation Opponents of a CTB argue that it would not be an important factor in non-proliferation. The potential nuclear weapon states of real concern would not sign such a treaty, they assert, since these states wish to maintain a nuclear weapons option. These countries have their own security concerns that have little or nothing to do with whether the United States and Soviet Union are continuing to improve their nuclear weapons. The pressure to join a CTB is further reduced by the fact that France and China most likely will not join such a treaty in the foresee- able future. Opponents also argue that potential nuclear weapon states will be able to develop a nuclear weapons option and even stockpile simple nuclear weapons without testing. In support of this contention, they

NUCLEAR TEST BANS 223 point out that Israel has apparently been able to develop a first genera- tion nuclear weapon without a test. Other countries may follow this example even if they join a CTB or are indirectly constrained by it from testing. Supporters of a CTB argue that it would be a key factor in creating a nuclear regime conducive to non-proliferation. Many non-nuclear weapon states have consistently and bitterly complained about the dis- criminatory nature of the present international nuclear regime. These states particularly object to the continuation of nuclear testing, which they see as a symbol both of the threat of nuclear war and of the inequi- table nature of the Non-Proliferation Treaty. Supporters argue that a CTB treaty would go a Tong way in the eyes of the non-nuclear weapon states to meeting the obligation that the United States and the Soviet Union undertook in Article VT of the NPT "to pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date." Many potential nuclear weapon states would sign a CTB treaty, ac- cording to supporters. Even those that chose not to sign would be uncler greatly increased international, and in some cases domestic, pressure not to undertake nuclear testing. Thus France, a nonsignatory to the Limited Test Ban Treaty, discontinued atmospheric testing in 1974. Despite the apparent example of Israel, these supporters contend that it would be much more difficult technically and politically for most coun- tries to develop a nuclear weapons capability without testing. This would be particularly true in countries without the technical expertise of Israel or in which the military did not have confidence in a relatively inexperienced scientific community. In any event, it would be ex- tremely difficult for present non-nuclear weapon states to go beyond relatively primitive first generation nuclear fission weapons without testing, and it would be impossible for them to develop thermonuclear weapons.

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This nontechnical overview of developments in nuclear arms control describes how the United States and the Soviet Union arrived at their present positions—and where they might go from here. According to Foreign Affairs, "This book is proof that the complexities of arms control can be successfully explained in a nontechnical, and even more importantly, nonpartisan manner....It presents the key issues in a clear, thorough, and remarkably up-to-date way....Strongly recommended as a primary source for classroom and public discussions."

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