U.S. Nuclear Weapons Policy and Nuclear Nonproliferation

U.S. Nuclear Weapons Policy and Nuclear Nonproliferation Christopher F. Chyba Department of Astrophysical Sciences and Woodrow Wilson School of Public and International Affairs, Princeton University A working paper for: International Implications for and Levers On U.S. Nuclear Weapons Policy U.S. Nuclear Policy Review Project The Stanley Foundation July 31, 2008 Abstract. Published analyses of the connection between U.S. nuclear weapons policy and nuclear nonproliferation reveal a host of diverging assertions. A systematic analysis is needed, but so far is lacking. This essay frames this analysis, and begins it. I argue that when assessing the proliferation effects of changes in U.S. nuclear weapons policy, it is necessary and useful to disaggregate the impact of U.S. policy on four categories of states: (1) the current nuclear powers; (2) determined proliferators; (3) nations relying on U.S. security assurances; and (4) other non-nuclear-weapon states. It may also be helpful to consider two cross-cutting categories, viz.: (5) states that have previously suspended nuclear weapons programs; and (6) the nuclear supplier states. Any upcoming revision of U.S. nuclear weapons policy should incorporate, as an intrinsic part of a nuclear policy and posture review, such an analysis of probable and possible impacts on the nonproliferation regime. 1

Introduction: A Host of Diverging Assertions George Shultz, William Perry, Henry Kissinger, and Sam Nunn asserted in their January 2007 editorial in the Wall Street Journal that a solid consensus for reversing reliance on nuclear weapons globally would be a vital contribution to preventing their proliferation into potentially dangerous hands. 1 In their 2008 follow-on editorial, these authors added: The accelerated spread of nuclear weapons, nuclear know-how and nuclear material has brought us to a nuclear tipping point. We face a very real possibility that the deadliest weapons ever invented could fall into dangerous hands. 2 Preventing this, they assert, requires a clear statement of the ultimate goal of nuclear disarmament: Without the vision of moving toward zero, we will not find the essential cooperation required to stop our downward spiral. 3 Both editorials presented concrete steps that should be taken in pursuit of nuclear disarmament and nuclear security. But neither went further than the previously quoted statement in explaining the causal connection between the pursuit of disarmament and the impact of this goal on preventing nuclear weapons proliferation. Skeptics were quick to reply that there is no such connection. In November 2007, the Wall Street Journal published a reply to the first Shultz et al. editorial by Harold Brown and John Deutch, titled The Nuclear Disarmament Fantasy. Brown and Deutch declared: A nation that wishes to acquire nuclear weapons believes these weapons will improve its security. The declaration by the U.S. that it will move to eliminate nuclear weapons in a distant future will have no direct effect on changing this calculus. Indeed, nothing that the U.S. does to its nuclear posture will directly influence such a nation s (let alone a terrorist group s) calculus. Nor would such steps, they asserted, convince North Korea, Iran, India, Pakistan or Israel to give up their nuclear weapons programs. 4 The Brown and Deutch reply echoed arguments that the Secretaries of State, Defense and Energy submitted to the Congress in their 2004 report An Assessment of the Impact of Repeal of the Prohibition on Low Yield Warhead Development [PLYWD] on the Ability of the United States to Achieve Its Nonproliferation Objectives. 5 In this report, the Secretaries argued that rogue state proliferation... marches forward independently of the U.S. nuclear program, and that North Korea and Iran appear to seek WMD in response to their own perceived security needs, in part, to deter the United States from taking steps to protect itself and allies in each of these regions. In this regard, their 1 George P. Shultz, William J. Perry, Henry A. Kissinger and Sam Nunn, A World Free of Nuclear Weapons, Wall Street Journal, January 4, 2007. 2 George P. Shultz, William J. Perry, Henry A. Kissinger and Sam Nunn, Toward a Nuclear-Free World, Wall Street Journal, January 15, 2008. 3 Ibid. 4 Harold Brown and John Deutch, The Nuclear Disarmament Fantasy, Wall Street Journal, November 19, 2007. 5 An Assessment of the Impact of Repeal of the Prohibition on Low Yield Warhead Development on the Ability of the United States to Achieve Its Nonproliferation Objectives, jointly submitted by The Secretary of State, The Secretary of Defense, The Secretary of Energy, to Congress in response to the National Defense Authorization Act for Fiscal Year 2004, Public Law No. 108-136, Section 3116, March 2004 [Hereafter, PLYWD, 2004 ]. 2

incentives to acquire WMD may be shaped more by U.S. advanced conventional weapons capabilities and our demonstrated will to employ them to great effect... than to anything the United States has done, or is doing, in the nuclear weapons arena. 6 Speaking specifically of PLYWD repeal, the Secretaries subsequently made the broader argument that there is no reason to believe that repeal has had or will have any practical impact on the pursuit of nuclear weapons by proliferating states, on the comprehensive diplomatic efforts ongoing to address these threats, or on the possible modernization of nuclear weapons by China or Russia. 7 Speaking at the American Academy in Berlin in June 2008, Senator Sam Nunn acknowledged that the four authors of the Wall Street Journal editorials don t believe [the U.S.] example is likely to inspire Iran, North Korea or al Qaeda to drop their weapons ambitions, but we believe it would become more likely that many more nations will join us in a firm approach to stop the proliferation of nuclear weapons and materials and prevent catastrophic terrorism....we cannot take these steps without the cooperation of other nations. We cannot get the cooperation of other nations without the vision and hope of a world that will someday end these weapons as a threat to mankind. 8 Harold Brown agrees with this last point. 9 Two senior participants in the Shultz et al. initiative, Sidney Drell and James Goodby, made a different argument in summer 2008, claiming that a vision for disarmament is intended to influence future decisions by countries considering nuclear weapons development: If decisionmakers [sic] think that some nations will still possess nuclear weapons or that more nations will acquire them and that possessing nuclear arsenals is going to be seen as normal and legitimate, they will logically lean toward keeping open the option to build a nuclear arsenal themselves and will exercise that option when conditions seem to require it. 10 The authors of Universal Compliance: A Strategy for Nuclear Security, make both the Nunn and the Drell and Goodby arguments, but with a focus on states that have given up nuclear weapons programs: Argentina, Brazil, Canada, Germany, Japan, South Africa, and Sweden are among the influential countries that demand clearer commitments to disarmament in order to ensure their continued cooperation in nonproliferation efforts. These states commitments to abjure nuclear weapons must not be taken for granted; in some cases it is conceivable that decisions could be made to hedge nuclear weapons options. More immediately, these states are vital to the making and enforcing of the rules on which effective nonproliferation depends. 11 6 Ibid., p. 4 7 Ibid., p. 10. 8 Sam Nunn, The Race Between Cooperation and Catastrophe, The American Academy in Berlin, Berlin, Germany, June 12, 2008, p. 2. 9 Harold Brown, New Nuclear Realities, The Washington Quarterly, Winter 2007-08, Vol. 31, No. 1, pp. 7-22. See p. 11: Reducing U.S. nuclear weapons deployments and stockpiles... will have little or no direct effect on the behavior of potential nuclear weapons states. Such policies and actions, however, can help gain international support for other measures that will. 10 Sidney Drell and James Goodby, The Reality: A Goal of a World Without Nuclear Weapons is Essential, The Washington Quarterly, Summer 2008, Vol. 31, No. 3, p. 30. 11 George Perkovich, Jessica T. Mathews, Joseph Cirincione, Rose Gottemoeller, and Jon B. Wolfsthal, Universal Compliance: A Strategy for Nuclear Security (Washington DC: Carnegie Endowment for International Peace, 2005), p.150. 3

Kathleen Bailey and coauthors have presented their views on the role of U.S. nuclear weapons and these weapons relation to proliferation. 12 They consider the first two roles of U.S. nuclear weapons to be to preserve peace and prevent coercion, and to deter the use of weapons of mass destruction. They state that The third role of the U.S. nuclear arsenal is to help prevent nuclear proliferation by extending our deterrent the nuclear umbrella. 13 The authors present a list of countries under the U.S. nuclear umbrella, either explicitly or, in the view of the authors, implicitly. They conclude that there are in 31 countries under the U.S. umbrella. They quote the NATO Alliance s Strategic Concept of April 1999 that states, The supreme guarantee of the security of the Allies is provided by the strategic nuclear forces of the Alliance, particularly those of the United States.... 14 Christopher Chyba and J.D. Crouch, in an essay summarizing key disagreements over U.S. nuclear weapons policy, report the Bailey et al. argument that the pursuit of nuclear disarmament could be harmful to nonproliferation objectives if it undermined nuclear assurances given to allies that rely on the U.S. security assurances, and contrast it with the arguments of those who emphasize the importance of Article VI of the 1968 Nuclear Non-Proliferation Treaty (NPT): Whereas those who favor working toward a world without nuclear weapons see an emphasis on nuclear arsenals as abetting nonproliferation by decreasing support for nonproliferation initiatives, those opposed worry that too much emphasis on abolition would itself drive proliferation, by signaling to states currently reliant on the U.S. umbrella that they may need to develop their own nuclear deterrent and by signaling to hostile proliferators a general retreat from U.S. political-military commitments. 15 The Need for a Comprehensive Analysis Even this small sample of writings on the connection between U.S. nuclear weapons policy and nuclear proliferation displays a host of diverging assertions, suggesting the need for a systematic analysis of the connection between U.S. nuclear weapons policy and nuclear proliferation (or nonproliferation). The goal of this essay is to frame this analysis, and to gesture at its beginning. Any upcoming revision of U.S. nuclear weapons policy should incorporate, as an intrinsic part of a nuclear policy and posture review, such an analysis of probable and possible impacts on the nonproliferation regime. It may seem odd to some even to suggest that such an analysis is necessary. After all, an explicit connection is made between disarmament and nonproliferation by Article VI of the NPT. This connection was strongly reaffirmed as a condition of the 1995 12 Kathleen C. Bailey, Robert G. Joseph, Gordon C. Oehler, Keith B. Payne, Robert L. Pfaltzgraff, Charles S. Robb, C. Paul Robinson, James R. Schlesinger, William Schneider, William Van Cleave, and R. James Woolsey, White Paper on the Necessity of the U.S. Nuclear Deterrent, updated August 15, 2007. 13 Ibid., p. 2. 14 NATO Press Release, The Alliance s Strategic Concept, 23 April 1999, paragraph 62. 15 Christopher F. Chyba and J. D. Crouch, Key Divergent Views on U.S. Nuclear Weapons Policy, presented at Strategic Weapons in the 21 st Century, Washington, DC, January 31, 2008 p. 8. 4

indefinite extension of that treaty, and given more specificity in the thirteen practical steps agreed to at the 2000 NPT review conference. Certain commitments, including to a Comprehensive Test Ban Treaty (CTBT) and Fissile Material Cutoff Treaty (FMCT), were made in 1995 by the nuclear weapons states as part of a package to obtain the NPT s indefinite extension, and it would seem deductively clear that fulfilling this bargain is of importance to maintaining the health of the NPT. Jayantha Dhanapala, President of the 1995 NPT extension and review conference, writes that The extension of the NPT was achieved largely because the long-stalled [CTBT], generally seen as the litmus test of nuclear disarmament, was close to adoption. He also adds that there is a tide of proliferation that arises from the political and military value attached to nuclear weapons. 16 Yet it also seems likely correct that there has been little connection between U.S. steps toward disarmament, and decisions taken by Iran or the Democratic People s Republic of Korea (DPRK) to move toward nuclear weapons. In their 2004 PLYWD report, the Secretaries argued that if anything, the historical evidence is for an anticorrelation:... there is no indication at all that very significant reductions in the numbers of U.S. (and Russian) nuclear weapons, and in the alert levels of nuclear forces, over the past decade, coupled with no U.S. nuclear testing and very little U.S. nuclear modernization, has caused North Korea or Iran to slow down covert programs to acquire capabilities to produce nuclear weapons. On the contrary, these programs have accelerated during this period. Nor did such U.S. restraint convince India and Pakistan not to test in 1998. 17 Moreover, it is at least plausible that certain U.S. allies could be pushed toward proliferation if they became sufficiently worried about the medium-term credibility of the U.S. nuclear umbrella. There is even the argument, presented in the leaked portions of the 2001 Nuclear Posture Review and the 2002 National Security Strategy that various military capabilities, including nuclear weapons capabilities, might dissuade certain countries either from choosing to proliferate or from attempting to match the U.S. in symmetric capabilities. Even apart from these assertions, however, the influence of nuclear weapons restraint on nuclear proliferation seems to point in several different directions at once. The Need for Disaggregation What is needed is to disaggregate categories of countries that we imagine influencing through U.S. nuclear weapons policy. By doing so, we may find that steps toward disarmament in U.S. nuclear weapons policy bring with them pressures both against and in favor of nuclear proliferation, depending on the countries being considered. At a minimum, we need to understand this landscape for the purpose of risk analysis for any proposed steps. Further, this suggests the need for a comprehensive strategy that seeks to maximize nonproliferation effects and minimize any proliferation drivers for any U.S nuclear weapons policy. For example, it may be necessary to supplement particular steps taken to reduce the salience of nuclear weapons in U.S. 16 Jayantha Dhanapala, Fulfill and Strengthen the Bargain, Arms Control Today Vol. 38, No. 5, June 2008, pp. 14-16. 17 PLYWD, p. 4. 5

foreign policy with additional efforts intended to offset any potential pressure toward proliferation that may result. I suggest that it is useful as a first step to consider dividing states into four categories. Of course, each category could be further subdivided and in fact, as a matter of practical diplomacy, would need to be. Moreover, there are at least two cross-cutting categories that are clearly of interest. But even the simple typology of four categories of states is analytically useful and demonstrates the value of taking a more systematic approach. In particular, when assessing the proliferation effects of changes in U.S. nuclear weapons policy including steps that would be viewed as consistent with the ultimate goal of nuclear disarmament we should consider the impact on the following four categories of states: (1) the current nuclear powers; (2) determined proliferators; 18 (3) nations relying on U.S. security assurances; and (4) other non-nuclear-weapon states. We should also consider two cross-cutting categories, viz. (5) states that have previously suspended nuclear weapons programs but are technically capable of reversing this decision; and (6) the nuclear supplier states. Current Nuclear Powers There are a number of important issues here concerning the role of U.S. nuclear weapons and doctrine including, perhaps most importantly, the role of U.S. ballistic missile defense programs on both the vertical proliferation and nuclear doctrines of the other nuclear powers including the P-5 as well as India, Israel, and Pakistan. This is a vast topic; just a few among many important issues would include the interaction between U.S. nuclear policy and Chinese strategic plans; 19 the ongoing evolution of the U.S-Russian strategic relationship; 20 or the role that U.S. nuclear use doctrine reportedly played in Indian Prime Minister Vajpayee s modifications of India s no-first-use pledge. 21 Beyond vertical proliferation questions lies the issue of the extent to which U.S. nuclear weapons policy influences these countries decisions regarding horizontal 18 I do not define determined proliferators to mean inevitable proliferators or even implacable proliferators; rather, a determined proliferator is simply a country that appears to be making a serious effort toward nuclear weapons or nuclear weapons capability. This policy may or may not prove to be reversible. 19 See, for example, Joanne Tompkins, How U.S. Strategic Policy Is Changing China s Nuclear Plans, Arms Control Today, January/February 2003. Tompkins analysis is based on more than 60 not-for-attribution interviews with Chinese government officials, arms control experts, military officers and journalists, and provides an indication of the kind of thorough study that will be needed to get at these issues while minimizing the risk of cherry picking this or that particular government official or office whose views accord with those favored by a particular U.S. analyst. 20 See, for example, Alexei Arbatov and Rose Gottemoeller, New Presidents, New Agreements? Advancing U.S.-Russian Strategic Arms Control, Arms Control Today, July/August 2008. 21 Summarized by Christopher F. Chyba and Karthika Sasikumar, A World of Risk: The Current Environment for U.S. Nuclear Weapons Policy, in George Bunn and Christopher F. Chyba, eds., U.S. Nuclear Weapons Policy: Confronting Today s Threats (Washington DC: Brookings Institution Press, 2006), p. 17. 6

proliferation decisions that range from the establishment and enforcement of their own physical protection and export control regimes, to their participation in multilateral initiatives and processes, to their willingness to support particular actions such as sanctions against countries that appear to be in pursuit of nuclear weapons. This subtopic similarly demands its own study; it appears, however, that advances in physical protection and export controls among the nuclear powers have been substantially insulated from issues of nuclear weapons posture, whereas decisions over specific questions of sanctions, for example, may more broadly reflect the overall relationship with the U.S. (including as a subset the nuclear relationship). Determined Proliferators There appears to be something close to a consensus among U.S. commentators that states such as Iran or the DPRK are not strongly affected in their pursuit of nuclear weapons options by the details of U.S. nuclear weapons policy. This would seem to undermine some hopes for dissuasion, e.g. as expressed in the 2001 Nuclear Posture Review, which reportedly stated that U.S. military forces, including nuclear forces, will be used to "dissuade adversaries from undertaking military programs or operations that could threaten U.S. interests or those of allies and friends. 22 To my knowledge, there is no evidence that Iran or the DPRK were dissuaded from their nuclear, chemical or putative biological programs by U.S. nuclear capabilities, though fears of military strikes may have played a role in the Clinton Administration s obtaining the Agreed Framework with the DPRK and in driving the programmatic and geographical diversity of Iran s nuclear initiatives. 23 Libya s complicated decision to renounce weapons of mass destruction may have been influenced by fear of the U.S. military, though again there is no evidence that U.S. nuclear capabilities played an important role. 24 There also appears to be something of a U.S. consensus, within the Bush Administration and without, 25 that U.S. conventional capabilities have provided a stronger driver for nuclear proliferation than nuclear weapons; this is something to consider with respect to the future role of prompt global strike capabilities. This author has heard an international colleague assert that, e.g., Iran s pursuit of nuclear weapons was a response to U.S. nuclear weapons, but this assertion was withdrawn when challenged. 22 Nuclear Posture Review [leaked excerpts], submitted to Congress on 31 December 2001, http://www.globalsecurity.org/wmd/library/policy/dod/npr.htm, p. 9. 23 This diversity was discussed by Chaim Braun and Christopher F. Chyba, Proliferation Rings: New Challenges to the Nuclear Nonproliferation Regime, International Security Vol. 29, No. 2., Fall 2004, pp. 49. 24 Bruce W. Jentleson and Christopher A. Whytock, Who Won Libya? The Force-Diplomacy Debate and Its Implications for Theory and Policy, International Security Vol. 30, No. 3., Winter 2005/06, pp. 47-86. 25 See, e.g., Kurt M. Campbell and Robert J. Einhorn, Avoiding the Tipping Point: Concluding Observations, in Kurt M. Campbell, Robert J. Einhorn, and Mitchell B. Reiss, eds., The Nuclear Tipping Point (Washington DC, Brookings Institution Press, 2004), p. 323. 7

Nations Relying on U.S. Security Assurances One divergence in internal U.S. thinking about the nonproliferation regime is whether the regime is more threatened (among the many other threats it faces) by a failure of U.S. leadership with respect to NPT Article VI obligations, or by a failure of U.S. assurance policy i.e. the confidence that regional friends and allies have in U.S. security commitments and, ultimately, the U.S. nuclear umbrella. 26 Campbell and Sunohara argue that the U.S. nuclear deterrence guarantee provides the most important reason why Japan has not sought to develop an independent nuclear weapons capacity. 27 Certain other countries that relied on the U.S. nuclear umbrella during the Cold War, such as Germany, seem unlikely to go nuclear under foreseeable circumstances. 28 The implications of case studies seems mixed though a thoroughgoing analysis is needed-- but were just one power nudged toward a nuclear weapons acquisition decision by changes in U.S. nuclear weapons policy, that would be a risk sufficient to merit grave concern and careful mitigating steps. Other Non-Nuclear Weapons States The final category is that of the vast majority of non-nuclear weapon states (NNWS) that are signatories to the NPT and which play a crucial role in the overall health of the regime whether through the vigor with which they adopt and implement UN Security Council Resolution 1540, their willingness to adopt the International Atomic Energy Agency (IAEA) Additional Protocol for inspections and monitoring, or their willingness to support sanctions or other steps against determined proliferators. Yet there appears to be far too little empirical work dedicated to understanding what role U.S. nuclear weapons policy actually plays in these nations decisions with respect to the nonproliferation regime. 29 Disentangling rhetoric from reality, and being conscious of how discovered answers to this question may depend on the desire of the analyst asking the question, or on the bureaucratic location of the NNWS official being asked, may prove especially challenging. (For example, one might worry that officials in a Ministry 26 This is discussed in Chyba and Crouch, Key Divergent Views. 27 Kurt M. Campbell and Tsuyoshi Sunohara, Japan: Thinking the Unthinkable, in Kurt M. Campbell, Robert J. Einhorn, and Mitchell B. Reiss, eds., The Nuclear Tipping Point (Washington DC, Brookings Institution Press, 2004), p. 236. For arguments that Japan is unlikely to go nuclear in the foreseeable future, see Benjamin L. Self and Jeffrey W. Thompson, eds., Japan s Nuclear Option: Security, Politics, and Policy in the 21 st Century (Washington DC, Henry L. Stimson Center, 2003). 28 An unamed German Ministry of Defense official said The security of Europe depended entirely on nuclear weapons, but Germany decided not to pursue them. We don t need them; we have NATO. I can t see any reason or international situation in which this would change.... In the new security environment of today, nuclear weapons play a less and less important role. Quoted in Jenifer Mackby and Walter B. Slocombe, Germany: The Model Case, A Historical Imperative, in Kurt M. Campbell, Robert J. Einhorn, and Mitchell B. Reiss, eds., The Nuclear Tipping Point (Washington DC, Brookings Institution Press, 2004), p. 212. 29 Andy Grotto s draft paper for this meeting is an important exception. See Andrew J. Grotto, What Drives States to Support New Nonproliferation Obligations? An Empirical and Theoretical Exploration. 8

of Foreign Affairs would be more likely to blame pursuit of nuclear weapons on U.S. nuclear weapons policy and Article VI failings, whereas individuals working on the technical program within an energy or defense ministry might in fact be motivated by, and cite, quite different drivers.) As Grotto 30 and others have pointed out, a small subset of these countries is especially influential and probably require the greatest study. Within the New Agenda Coalition (credited with driving the 13 steps agreement at the 2000 NPT Review Conference) these include, especially, Egypt and South Africa. South Africa, for example, reportedly holds 400-450 kg of ~80% HEU in storage at Pelindaba (under IAEA monitoring), and has stated at recent international nonproliferation conferences that, while it is not opposed in principle to minimizing the civilian use of HEU (therefore supporting an important nonproliferation goal), South Africa views this goal as linked to the elimination of excess military stockpiles of the nuclear weapons states. 31 Cross-Cutting Categories There are cross-cutting categories of states that should be considered as well. One such category is the list of nuclear-capable states, either the list of nearly 50 current nuclear-capable states, 32 or those that reversed their earlier pursuit of nuclear weapons. 33 Outside the determined proliferators category, and assuming that nuclear transfer can be prevented, these states are those of most direct concern when considering the putative effects of U.S. nuclear weapons policy on proliferation decisions. Similarly, the nuclear supplier states are of greatest interest with respect to the putative role of U.S. nuclear weapons policy on decisions to proliferate relevant technology though here it must be remembered that, increasingly, non-traditional supplier states such as Malaysia (recalling SCOMI Precision Engineering s role in the A.Q. Khan network) are of importance as well. 34 Conclusion There is a clear and powerful diplomatic connection, embodied in Article VI of the NPT (and in that treaty s indefinite extension) between U.S. (and, of course, other P- 5) nuclear weapons policy and nuclear nonproliferation. The Article VI connection, however, only captures part of the story. With respect to certain states, moves toward nuclear disarmament may have little influence on proliferation objectives, or in some cases might even provide pressure toward proliferation. This does not mean that substantial reductions in U.S. nuclear weapons, or other steps (such as CTBT ratification) 30 Ibid. 31 Frank von Hippel, personal communication (July 2008). 32 See Jacques E.C. Hymans, The Psychology of Nuclear Proliferation: Identity, Emotions, and Foreign Policy (Cambridge: CUP, 2006), p. 4; for a discussion of the criteria comprising nuclear-capable, see Stephen M. Meyer, The Dynamics of Nuclear Proliferation (Chicago, U. Chicago Press, 1984), Appendix B. 33 See, for example, Ariel Levite, Never Say Never Again: Nuclear Reversal Revisited, International Security Vol. 27, No. 3, Winter 2002/03, pp. 59-88. 34 Braun and Chyba, Proliferation Rings. 9

consistent with NPT Article VI should not be pursued. It does mean that as the United States does so, it should be clear about what it hopes to achieve, clear about what such steps will not achieve, and pay close attention to the mitigation of any new proliferation risks. The current U.S. posture, which gives the impression of having expanded the potential circumstances under which, and countries against whom, nuclear weapons might be used, clearly also carries its own potential proliferation risks. Our objective should include mitigating these risks as part of a careful overall change in U.S. nuclear posture. The goal of this essay has been to sketch an analytical approach to further this objective. 10