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APPENDIX E
Nuclear Weapons in Post-Cold War Deterrence
INTRODUCTION: A DEFINITION OF DETERRENCE
"The current questioning of nuclear deterrence implies something other than its withering away. There is no post-nuclear strategy. . . .[T]he nuclear instrument remains the central element in the defense of the nuclear powers."2Perhaps in today's environment, only a French analyst would be bold enough to make this argument publicly. There is a perception in the United States that nuclear weapons are a burdensome legacy of the Cold War that have lost their relevance and perhaps become counterproductive to American and international security. Deterrence, it is argued, is still vital to U.S. national security strategy, but perhaps it can be achieved by a combination of actions ranging from preventive diplomacy to military deterrence by means of modern conventional weaponry.
Few would disagree that conventional forces will play a greater part in deterrence in the future. But, in fact, as several thoughtful scholars have pointed out, the jury is still out on whether nuclear weapons can be dispensed with in the post-Cold War world.3Will conventional deterrence be enough, or will nuclear weapons continue to fill a unique niche? If so, what will be required to sustain an adequate American nuclear deterrent? Here we review the meaning of deterrence and the relative capabilities of nuclear and conventional forces to satisfy remaining deterrence needs for the United States for the foreseeable future. Admittedly, the decision to retain or reject nuclear weapons has become a complex problem with the end of the Cold War era, and there are arguments on both sides of the question that need to be taken into account. One thing that is certain is that there is now a high level of geopolitical uncertainty in the world. Much remains to be decided, both in the evolving relations among states
1 The views expressed here are the authors' own and do not reflect those of the Department of Energy.
2 Boyer, Yves. 1993. "Questioning Minimal Deterrence" in Serge Sur, ed., Nuclear Deterrence: Problems and Perspectives in the 1990s, pp. 101-104, United Nations, New York.
3 See, for example, George H. Quester and Victor A. Utgoff, "No-First-Use and Nonproliferation: Redefining Extended Deterrence," Washington Quarterly, Vol. 17, no. 2, pp. 103-114, Spring 1994. The authors argue that not only nuclear weapons but also an implicit threat of nuclear first use will be required into the foreseeable future.
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and in the responses of the United States to those developments, which will profoundly affect the need for deterrence strategies and nuclear weapons, and the wisdom of further nuclear disarmament. We believe that this uncertainty means proceeding cautiously; we conclude that nuclear weapons should retain an attenuated, but still important, role in U.S. national security policy for the time being.
Meaning of "Deterrence"
It is widely agreed today that "deterrence" as a term of art means preventing war either through fear of punishment or fear of defeat, or sometimes even through fear of undefined negative consequences. The word "deterrence" is derived from the Latin de + terrere, literally "to frighten from" or "to frighten away." Thus, fear is central to the original meaning of deterrence. The idea that vast, indiscriminate, and unacceptable damage would be inflicted in retaliation for aggression, as was associated with the prospect of the aerial bombing of open cities in the 1930s, or the employment of nuclear weapons since World War II, has long been central to the popular understanding of the term deterrence. That fear of defeat could be powerfully deterring, although a longstanding idea, has been less widely understood.
Nuclear deterrence both as a concept and as practical doctrine had several variations during the Cold War. These included the declared doctrine of massive retaliation, with its stark punitive threat and heavy reliance on the strategic nuclear air offensive. The mature U.S. nuclear strategy, which obtained from the 1960s until the collapse of the Soviet Union, was extended nuclear deterrence. Under this doctrine, the United States deterred direct attack upon itself with strategic nuclear forces, while extending protection to its Cold War allies and friends by promising to escalate a war to the nuclear level if they were in danger of defeat by Soviet-led forces, even if this entailed first use of nuclear weapons by the United States. Extended deterrence was achieved via the "seamless web" of conventional, theater, and strategic nuclear forces. Although this strategy did have an important conventional component, it ultimately depended on the threat of escalation to large-scale nuclear use. One interesting late variation on the theme of extended nuclear deterrence was that the fear that deterred could be a threat to destroy not urban-industrial areas per se but those items the opposing regime valued most. In the case of the Soviet Union, this was postulated to be the survival of the regime itself and its ability to preserve and perpetuate its control over the Soviet state. Another variation was that deterrence could be strengthened by posing the threat that the Soviets' strategic nuclear strike would not succeed because of the operation of U.S. strategic missile defenses, especially if linked to the prospect for subsequent punishment. It is also true that the idea of deterrence was subsumed within a system of mutual deterrence because of the deployment of large-scale Soviet nuclear forces in the 1950s and 1960s. However, neither mutuality nor parity is a necessary or inherent characteristic of the concept of deterrence.
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The idea that effective deterrence could be accomplished by conventional forces alone began to emerge in the mid-1980s.4At that time, it was based in part on questions about the efficacy of extended nuclear deterrence in the presence of a massive and growing Soviet nuclear arsenal and in part on improving the conventional defense capabilities of the United States and NATO.
Deterrence vs. Dissuasion
Some uncertainty has emerged over the breadth of coverage of the term deterrence. The definition of deterrence is expanding to include more than military threats. Those who argue for a more expansive definition believe that deterrence should be modified to include all instruments of national security, not merely the threat of military force. These might include nonmilitary sanctions, foreign policy initiatives, economic measures, and positive inducements. On the other hand, some have persuasively argued that the term "dissuasion" should be used to refer to a broader spectrum of deterring actions than those narrowly associated with military deterrence. The word dissuasion derives from the Latin dis + suadere, "to advise or persuade against," and is clearly more comprehensive in meaning than deterrence.
It is certainly proper to think about national security in this encompassing way and to remember that military deterrence is but one component of national strategy. During the Cold War, for example, deterrence was by no means identical with containment, although nuclear deterrence played a constant, everpresent, and central role in making containment possible. Following the Cold War, U.S. objectives to promote peace and enlarge the influence of democracy have relied heavily on diplomacy and multilateral actions. Military deterrence remains an important U.S. tool, but nuclear weapons have now assumed an unstated (but powerful) supporting role, while American, allied, and multilateral conventional forces currently supply the bulk of day-to-day deterrence.
For the purpose of understanding deterrence in the post-Cold War era, however, it is better not to encumber analysis with too broad a definition of deterrence. Coming to terms with a concept of deterrence that spans punishment and defense, conventional and nuclear weapons, in a multinational setting, is a large enough task without making deterrence synonymous with national security policy or foreign policy.
NUCLEAR VS. CONVENTIONAL DETERRENCE
Nuclear Deterrence
Deterrence emerged in its modem form in the 1930s in the context of the newfound capability to attack the whole of an enemy's civilian population and
4 Following on John Mearsheimer's examination of conventional deterrence in historical context and on the NATO-Warsaw Pact front (John J. Mearsheimer, Conventional Deterrence, Cornell University Press, Ithaca, N.Y., 1983).
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civil infrastructure without first defeating its ground and naval forces. Airplanes and dirigibles were first used militarily in World War I and were employed to attack cities almost as soon as they were used for reconnaissance and attacks on the battlefield. Although the impact of these terror attacks was minor, the development of air power in the 1920s and 1930s allowed for the theories of Douhet and other military strategists. Their theory of strategic air warfare argued that air forces could by themselves conduct a strategic campaign against the vital elements of state power that could win a war, with little or no involvement by ground and naval forces.5 The implications of this theory led to the emergence of the theory of deterrence as we know it.
In 1932 the British Prime Minister, Stanley Baldwin, reflected in horror on the theory of air attack as understood at that time: ''I think it is well also for the man in the street to realize that there is no power on earth that can protect him from being bombed. Whatever people may tell him, the bomber will always get through. . . . " Accordingly, "[t]he only defense is in offense, which means that you have to kill more women and children more quickly than the enemy if you want to save yourselves."6 On the basis of arguments like these, Britain engaged belatedly in the creation of a bomber-heavy air force that, it hoped, would serve to deter rather than actually fight a new world war.
As it turned out, both sides in World War II resorted early to urban bombing.7Conventional bombing could be defended against to some extent; the prospect of strategic conventional bombing did not deter war, nor was strategic bombing by itself able to secure the defeat of the opposing side (even though, eventually, the fire-bombing of Dresden and Tokyo, and the devastating thousand plane raids, approached nuclear strikes in the magnitude of damage they inflicted).
The lessons of World War II changed abruptly with Hiroshima and Nagasaki. Nuclear weapons clearly threatened damage that was unacceptable by any definition and would be almost impossible to defend against. Bernard Brodie, in his book The Absolute Weapon, in 1946, swiftly developed the theory of nuclear deterrence.8
Although nuclear weapons certainly played a major role in preventing major conflict during the Cold War, several problems emerged that increasingly cast doubt on the long-term utility of nuclear deterrence as the foundation of
5See, for example, David MacIsaacs, "Voices from the Central Blue: The Air Power Theorists," in Peter Paret, ed., Makers of Modern Strategy: From Machiavelli to the Nuclear Age, Princeton University Press, Princeton, N.J., 1986.
6Stanley Baldwin, House of Commons, Debates, 5th Series, Vol. 270, cols. 630-638.
7 Urban bombing was driven, in part, by a desire to encourage popular unrest and to make the casualties a burden on the government and in part by the inability to accurately deliver bombs against key strategic targets such as military installations and war-supporting industries. This was a particular problem for the British after they moved to nighttime bombing to reduce their losses to German defenses.
8 Brodie, Bernard. 1946. The Absolute Weapon: Atomic Power and World Order, Harcourt, Brace and Co., New York, pp. 74-83.
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U.S. security policy. The first problem is related to the massive destructive power of nuclear weapons. In the early days, large-scale destruction was considered an advantage, since large targets, like cities, could be struck and destroyed using a small number of bombs delivered with poor accuracy. Some even spoke of widespread collateral effects as "bonus damage." But as interest grew in attacks that could be discriminating and limited, collateral damage needed to be reduced: the previous virtue of nuclear weapons became a limitation. Moreover, the deployment by the Soviet Union of its own nuclear forces quickly put in place a mutual deterrence relationship, where the United States had to persuasively establish the credibility of its use of nuclear weapons, both in retaliation and in a first-use mode, even though the expected strike from the Soviets would inflict enormous damage on the U.S. homeland. Partly because of these developments, the U.S. public came increasingly to question nuclear weapons as the basis for its security while America's European allies grew skeptical of the notion of extended deterrence.
The end of the Cold War raised more doubts. Maintaining a ready nuclear strike force when the putative enemy had become a potential partner and seemed to be on the path to democracy appeared unwarranted. Moreover, continuing to rely heavily and directly on nuclear forces could be seen as reinforcing the idea that nuclear weapons have utility in assuring a nation's security interests, an argument that undermines our desire to make these weapons unattractive to potential proliferant states.
Deterrence After the Cold War: Are Conventional Forces Enough?
In light of this questioning of nuclear deterrence, Les Aspin (when he was still chairman of the House Armed Services Committee) coalesced a good deal of thought in the defense community that holds that, since the collapse of the Soviet Union, the United States possesses overwhelming conventional power. For that reason, Aspin argued, the United States would benefit from the worldwide elimination of nuclear weapons, if it were possible.9 At the same time, there is growing interest in the proposition that technology may now make it possible for the United States to achieve deterrence using conventional forces and weapons alone.10
A number of significant improvements have been made in the technology of conventional weapons in recent years, notably in accuracy, stealth, intelligence, and information support. Nor does the current theory of conventional deterrence require that conventional weapons be as powerful, destructive, or fearful as nuclear weapons. Rather, it is argued that sophisticated nonnuclear weapons can now hold at risk those assets most highly valued by
9 Aspin, Rep. Les, Chairman, House Armed Services Committee, From Deterrence to Denuking: Dealing with Proliferation in the 1990s. Informal paper given at the Paul Nitze School of Advanced International Studies, February 18, 1992.
10 For example, John A. Warden III, The Air Campaign: Planningfor Combat. Brassey's U.S., 1989.
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potential aggressors, for example, the enemy's leaders' lives (viz., the apparent success of the U.S. strike on Libya), their military forces, key elements of the aggressor state's civil infrastructure (as in Iraq), and so on. Of course there are critics who believe that, although conventional strike technologies have come a long way in recent years, there are still many important capabilities that can effectively be protected against current and foreseeable conventional weapons. Desert Storm, they point out, was not characteristic in that it was fought after long and careful preparation, in open desert, with effective basing and logistical as well as political support nearby. The absence of these factors could reduce the potency of conventional weapons against different opponents, to say nothing of the fact that many of the units in operation against Iraq have now been disbanded.
Congressman Aspin and others have also noted that non-Western leaders may operate upon different systems of belief and with different perceptions of reality than those that are inherent in, and have apparently worked well as a part of, nuclear deterrence. Thus, they may not accurately perceive U.S. capabilities or resolve and may not be deterred by our nuclear weapons. This line of reasoning by no means proves that deterrence is impossible against such leaders. Even Saddam Hussein declined to use his stocks of chemical weapons against the United States and its allies, deterred by some combination of factors that may well have included the possibility of nuclear retaliation, by either the United States or Israel. If there is a risk that a foreign leader will misperceive the power and decisiveness of U.S. deterrence capabilities, it probably is greater with conventional forces than with nuclear. On the other hand, U.S. resolve to use conventional as opposed to nuclear weapons is probably much more palpable to such leaders.
An important concern with conventional deterrence is that it has not always worked in the past, and it is not obvious even now that conventional force can have deterrent power that approaches that of nuclear weapons (although, as noted, the threat to use overwhelming conventional force may be much more credible). Conventional war à outrance in World War I, terrible as it was, did not deter the leaders of Germany and Japan from embarking on World War II. On the other hand, deterrence seems to have worked vis-à-vis the Soviet Union and against the Warsaw Pact, where nuclear weapons were directly implicated, although it did not prevent war in Korea, Vietnam, or Iraq (even if it helped to deter escalation), where nuclear weapons were a distant and vague threat.
Conventional deterrence also must face a number of practical problems. First of all, it requires a large and credible power projection capability because of the simple facts of geography. The United States does have a vital interest in the configuration of power in Europe and Asia. Being able to intervene in these areas militarily in order to protect U.S. interests is hard and expensive, entailing a complex of naval, air, and ground forces and their support. To operate these forces effectively requires an overseas base network, which we are losing, and a forcible entry capability, which is doubly challenging especially if there are no local bases to rely on. And as the Bottom-Up Review reminded us, even in the
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post-Cold War era, our security requirements demand a large standing force structure, and technological superiority, to assure the success of conventional campaigns.11 Not surprisingly, such complex, capable, and large forces prove to be very costly.
Another concern is that it is probably impossible to assure complete and reliable nuclear disarmament. Nuclear weapons are easy to hide, and it has even proven difficult to demonstrate the existence of nuclear weapons development and production capabilities to the extent necessary to justify intervention. The credibility of a threat by the United States to deploy conventional forces alone against small powers that may possess weapons of mass destruction, perhaps including nuclear weapons, is problematic.
It is often argued that a U.S. move to conventional deterrence might induce nuclear disarmament and prevent nuclear proliferation, but it is also plausible that nuclear disarmament by these powers would encourage or reward nuclear proliferation by rogue states or by those states that now take shelter under the umbrellas of the nuclear powers. A lesson that some foreign leaders and militaries learned from the Gulf War was that nuclear weapons may be necessary in order to offset otherwise overwhelming U.S. conventional capabilities.12
Conclusion: Nuclear Weapons Remain a Necessary Component of U.S. Deterrence
In light of the international situation and U.S. security interests as we can now know them, it seems impossible to safely remove nuclear weapons from U.S. deterrence calculations for the next 15 to 20 years. There is too much uncertainty to see beyond that period. There have indeed been historic, unforeseeable changes in the world situation over the past decade, and so we should not rule out further changes that could allow for further nuclear disarmament compatible with U.S. security, or perhaps even the shift of nuclear weapons into some form of international control regime. But in the present state of turmoil and uncertainty, complete elimination of nuclear weapons, or their entire removal, would be very unwise.
DETERRENCE VIA NUCLEAR WEAPONS IN THE FUTURE
Current U.S. Nuclear Policy
The United States now maintains a reduced but survivable, highly capable nuclear force that is in a nearly ready but not hair-trigger status (intercontinental and submarine launched ballistic missiles have been detargeted, bombers have
11 Bottom-Up Review: Analysis of Key DOD Assumptions, NSIAD-95-56, U.S. General Accounting Office, Washington, D.C., January 31, 1995.
12 Garrity, Pat. 1994. Gulf War Lessons Learned, Center for National Security Studies, Los Alamos National Laboratory, Los Alamos, N. Mex.
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been taken off day-to-day alert, and so on). The nuclear force is available in the event it is needed again to deter Russia (or China), neither of which is now an enemy state, but both of which have significant arsenals of weapons of mass destruction. The ability to upload a number of additional weapons is also retained as a hedge against an unexpected surge in Russian nuclear capabilities.13 Moreover, nuclear weapons have not been ruled out as a response to the use of nuclear, chemical, or biological weapons against the United States, and we still deter aggression against U.S. forces and allies overseas in part with nuclear forces. Officially, by treaty, the United States renounces the use of nuclear weapons against nonnuclear states that are not allied with nuclear-armed states. In practice, the U.S. nuclear posture implicitly supplements deterrence of all military challenges to U.S. security interests, even from nonnuclear Third World states.
Future Options for Nuclear Deterrence
The option the authors prefer is a modest extension of current U.S. deterrence policy; the United States should express an intention to apply nuclear weapons specifically to the deterrence of nuclear challengers (nuclear weapons to deter the use of nuclear weapons). At the same time, the United States should not take steps (or make statements or pledges) that in practice would completely exclude nuclear retaliation from the calculations of nonnuclear states, especially so-called rogue states that may possess chemical or biological weapons and that may contemplate challenges to U.S. security. The nuclear forces of the nuclear weapons states could be smaller, with the relationships among those arsenals set by explicit or tacit agreement. The United States probably can safely eliminate specifically "tactical" nuclear weapons (the removal of weapons from Europe is a sensitive, symbolic political issue to be decided by the needs of the NATO states). Remaining U.S. nuclear weapons would be able (though not optimized) to serve both strategic and tactical deterrence. The United States would attempt to make its nuclear weapons fade into the background, in order not to weaken its hand unduly in advocating nonproliferation, but the nuclear force would remain in the shadows as a potent deterrent.
An alternative approach would be for the United States to retain adequate nuclear weapons capability and credibility to continue to support extended nuclear deterrence by means of a policy of flexible response. This would differ mostly in the retention of a more visible, but not necessarily larger, nuclear force and perhaps retention of a small, dedicated set of theater nuclear weapons. Such an alternative would be less attractive to the extent that it underscores our belief that nuclear weapons confer major national security benefits, and dilutes our nonproliferation activities.
An option widely explored is to move to a minimal or existential deterrence posture and policy, retaining either a very small alert nuclear force, an off-alert
13Department of Defense, Office of the Secretary of Defense, Nuclear Posture Review briefing, Washington, D.C., September 22, 1994.
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force, or even dismantled forces that could be reactivated if the security situation demanded it. How small a nuclear force can be and still sustain effective deterrence is not known, but it is clear that for operational reasons it is difficult and expensive to go below some lower limit (e.g., at what level is it no longer technically or economically feasible to sustain a ballistic missile submarine fleet?). Nor is it likely that the United States will agree to reductions below those that the Russians would accept or that would bring the Chinese near nuclear parity. The proposal to dismantle all nuclear forces but retain them for a rainy day suffers from some of the same problems as complete nuclear disarmament. It adds to the concern that our capacity to restore these forces would atrophy while we continued to believe, perhaps inaccurately, that a nuclear deterrent force could readily be reconstituted. There is also the risk that a decision to reconstitute nuclear forces would exacerbate rather than stabilize a major crisis, either increasing the likelihood of war or dissuading the United States from rearming.
Finally, there has long been a constituency, given greater prominence by the end of the Cold War, that would like to see the United States and the other nuclear powers completely abandon nuclear weapons and denuclearize by agreement, with inspections and safeguards. Although there is some support for this proposal in the United States, it appears very unlikely, especially given the considerable interest of the French, British, Chinese, and Russians in continued reliance on their own nuclear forces. An alternative to denuclearization is to vastly reduce the number of nuclear weapons and to deliver the remaining weapons into the hands of an international peacekeeping organization, thereby retaining the utility of nuclear weapons in deterring all forms of war, while eliminating nuclear weapons as instruments of national policy. However, it is implausible that the nuclear states are prepared to relinquish their sovereignty and control over their ultimate security interests to an international body, as this proposal would require.
REQUIREMENTS FOR MAINTAINING NUCLEAR DETERRENCE
If the United States pursues a course of action that requires some continuing reliance on nuclear weapons, several technical and policy steps are essential. First and foremost, the United States should do its utmost to retain an adequate conventional force posture and superior conventional force technology. The more capable American conventional forces are, the less important nuclear weapons seem and the less the United States will need to rely on them. However, it is optimistic to believe that the United States will retain an adequate level of conventional forces, the determination to use them, and the ability to accept casualties that normally accompany conventional conflict, such that we could safely reduce our nuclear force, to an existential deterrent. Moreover, since conventional forces do not have the full deterrent power of nuclear weapons, they probably would not be acceptable to counter existing or future threats from nuclear weapons or other weapons of mass destruction.
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Nevertheless, the United States should try to place nuclear weapons in the background, making it known that they are viewed only as a final guarantor of vital U.S. national interests (which include due regard for the security of U.S. allies and friends). The United States need seldom or never explicitly raise a nuclear threat, whereas it should continue to try to suppress nuclear proliferation. Although perhaps not as clear-cut as some would like, this would be a simple, understandable, and believable policy (both for the American people and for those to be deterred). We need not, indeed should not, provide a detailed description of exactly when, under what precise conditions, or against which targets nuclear weapons might be used. In sum, a nuclear force somewhat smaller than today's, in conjunction with powerful conventional forces, should be capable of achieving U.S. security objectives in the world we now foresee.
Some sort of hedge against an increasingly hostile international environment is also important. The Defense Department advocates retaining some nuclear forces in reserve for a nuclear hedge. In addition, the United States should retain a capability to design, produce, and maintain nuclear weapons, although this, too, should be kept only as large as is necessary to meet national needs and should also be moved into the background. The need to do so is being addressed today under the rubric of stockpile stewardship. This program includes the maintenance of a much smaller stockpile than in the past, plus retention of the technical expertise necessary to understand and support the current stockpile. The Department of Energy, with the cooperation of the nuclear weapons complex, is developing a program that tries to fulfill these requirements.
No one knows whether there will ever be another requirement for new, or different, nuclear weapons. The present weapons, which were designed to address Cold War threats, certainly are not what one would design today for the 21 st century. Be that as it may, in the world that prevails, it is only prudent that the United States retain some capability, across the board, to address the concerns or problems of the arsenal as they arise.
If the world situation continues to relax, the role of nuclear weapons in U.S. security could again be reviewed and the nature of the nuclear complex required to support it reconsidered. But we should always be cautious with those forces that are the core of our deterrence policy. In this regard it is useful to remember the lesson of the British Ten-Year Rule. Following the allied victory in World War I and the Versailles Treaty, the British Cabinet decided that defense planning could proceed on the assumption that a major war would not occur for the next 10 years. This was a safe assumption at the time, which allowed for significant savings during the interwar years. But the Ten-Year Rule was then allowed to become rolling guidance: the need to begin reconstructing British military forces was constantly pushed at least 10 years into the future. When the new threat did begin to emerge in the early 1930s, the British were perilously tardy in responding. They were too late to deter war, and almost too late to avoid defeat.
