Exporting the Bomb: Technology Transfer and the Spread of Nuclear Weapons

By Matthew H. Kroenig

In a vitally important book for anyone interested in nuclear proliferation, defense strategy, or international security, Matthew Kroenig points out that nearly every country with a nuclear weapons arsenal received substantial help at some point from a more advanced nuclear state. Why do some countries help others to develop nuclear weapons? Many analysts assume that nuclear transfers are driven by economic considerations. States in dire economic need, they suggest, export sensitive nuclear materials and technology—and ignore the security risk—in a desperate search for hard currency.

Kroenig challenges this conventional wisdom. He finds that state decisions to provide sensitive nuclear assistance are the result of a coherent, strategic logic. The spread of nuclear weapons threatens powerful states more than it threatens weak states, and these differential effects of nuclear proliferation encourage countries to provide sensitive nuclear assistance under certain strategic conditions. Countries are more likely to export sensitive nuclear materials and technology when it would have the effect of constraining an enemy and less likely to do so when it would threaten themselves. In Exporting the Bomb, Kroenig examines the most important historical cases, including France's nuclear assistance to Israel in the 1950s and 1960s; the Soviet Union's sensitive transfers to China from 1958 to 1960; China's nuclear aid to Pakistan in the 1980s; and Pakistan's recent technology transfers, with the help of "rogue" scientist A. Q. Khan, from 1987 to 2002. Understanding why states provide sensitive nuclear assistance not only adds to our knowledge of international politics but also aids in international efforts to control the spread of nuclear weapons.

• Language: English
• Publisher: Cornell University Press
• Release date: Oct 15, 2011
• ISBN: 9780801457678

Book preview

Exporting the Bomb

Technology Transfer and the Spread of Nuclear Weapons

Matthew Kroenig

Cornell University Press   Ithaca and London

Contents

Acknowledgments

List of Abbreviations and Acronyms

Introduction: The Problem of Nuclear Assistance

1. Explaining Nuclear Assistance

2. The Correlates of Nuclear Assistance

3. Israel’s Nuclear Program: French Assistance! and U.S. Resistance

4. Common Enemies, Growling Dogs, and A. Q. Khan’s Pakistan: Nuclear Supply in Other Countries

5. Importing the Bomb: Nuclear Assistance and Nuclear Proliferation

Conclusion: Preventing Nuclear Proliferation

Appendixes:

A. Data Appendix for Chapter2

B. Data Appendix for Chapter5

C. Cases of Sensitive Nuclear Assistance

D. Selected Cases of Nonsensitive Nuclear Assistance

E. Selected Cases of Nonassistance

Bibliography

Acknowledgments

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This book traces its origins to work I performed as a military analyst in the U.S. government.¹ I was drafting a strategic assessment on how great powers would react to a particular nuclear proliferation issue and was surprised by my own analysis. We often hear that nuclear proliferation poses a general threat to international peace and security and that, for this reason, great powers can work together to combat the threat of nuclear proliferation. Yet, with the issue I was working on, I found great variety in the way countries approached the problem: some countries seemed very threatened by nuclear proliferation and were willing to do almost anything to stop it, others seemed less concerned, and still others were actually helping other countries develop their nuclear weapons programs. I could not understand why countries took such different approaches to what is often thought to be a common problem of nuclear proliferation. More important, I wanted to know why some countries were willing to go so far as to help other countries acquire the deadliest weapons known to mankind. This book is the result of that initial curiosity.

A variety of individuals and institutions played a significant role in the production of this book. I owe a special debt of gratitude to advisors in the Department of Political Science at the University of California at Berkeley. Steve Weber taught me that an argument can be creative, provocative, and correct, all at the same time. I thank M. Steven Fish for his thoughtful guidance on navigating the academy and the wider world beyond it. I thank Giacomo Chiozza for his invaluable advice on measuring and quantitatively analyzing international political events. Michael Nacht provided deep knowledge on nuclear weapons and arms control issues, along with a neverending supply of anecdotes about the policymakers whom I was studying.

An early fellowship with the Institute on Global Conflict and Cooperation (IGCC) at the University of California convinced me that nuclear proliferation was a subject that demanded further scholarly inquiry. I thank Susan Shirk for her work in establishing the Public Policy and Nuclear Threats Program at the IGCC and for saving me from writing on a less important topic.

A research workshop sponsored by the Committee for the Analysis of Military Operations and Strategy helped me to refine my proposal. I thank Stephen Biddle, Elizabeth Kier, and Dan Reiter for their detailed comments on my prospectus.

I spent a year as a fellow at the Center for International Security and Cooperation at Stanford University. I thank Lynn Eden for welcoming me into the vibrant intellectual community that she has helped to create there. I am also deeply indebted to Scott Sagan, whose insights and expertise on the scholarly study of nuclear proliferation assisted me at every stage of this project, all the way from helping me to settle on a question at the beginning of my research to reading and commenting on the entire manuscript upon its completion.

A postdoctoral fellowship in the Managing the Atom Project and the International Security Program at the Belfer Center for Science and International Affairs at Harvard University provided me with the uninterrupted time and supportive environment that helped bring this project to fruition. I thank Steve Miller and Martin Malin for the opportunity to participate in their programs and to take advantage of Harvard’s many resources.

I am also grateful for comments provided on this research project over the years by Graham Allison, Victor Asal, Naazneen Barma, Kyle Beardsley, Matthew Bunn, Alisa Carrigan, Ashton Carter, Jonathan Caverley, Alex Downes, Brent Durbin, James Fearon, Edward Fogarty, Matthew Fuhrmann, Erik Gartzke, Charles Glaser, Ron Hassner, Siegfried Hecker, John Holdren, Robert Jervis, Peter Katzenstein, Sarah Kreps, Sean Lynn-Jones, Alex Montgomery, Danielle McLaughlin, John Mearsheimer, Jonathan Monten, Patrick Morgan, John Mueller, Tatishe Nteta, Robert Pape, David Patel, Robert Powell, Ely Ratner, Phillip Roessler, Todd Sechser, Jacob Shapiro, Harold Smith, Regine Spector, Paul Stockton, Kevin Wallsten, Christopher Way, Stephen Walt, Dean Wilkening, and Zachary Zwald. My apologies to anyone I forgot.

I have also benefited from generous financial support. I thank the Charles and Louise Travers Department of Political Science at U.C. Berkeley; the Institute of International Studies at U.C. Berkeley; the Institute on Global Conflict and Cooperation at the University of California; the National Science Foundation; the Center for International Security and Cooperation at Stanford University; and the Project on Managing the Atom and the International Security Program at the Belfer Center for Science and International Affairs at Harvard University.

As I was finishing the manuscript, I was also able to benefit from comments at several research seminars across the country. I am grateful for helpful feedback from participants at seminars at the Olin Institute for Strategic Studies at Harvard University, the Program on International Security Policy at the University of Chicago, and the Center for International and Security Studies at the University of Maryland.

Parts of this book previously appeared in academic journal articles. I thank Cambridge University Press and Sage Publications for the permission to reprint this material.²

For helping this book through the publication process, I am grateful to Roger Haydon, the editors of the Cornell Studies in Security Affairs Series, and the staff at Cornell University Press. I also thank two anonymous reviewers for their constructive comments.

Last, but not least, I thank my family. My parents, Mark and Barb Kroenig, and my siblings, Brad and Julie Kroenig, have been an endless source of support, encouragement, and inspiration in everything that I have ever done. This book is dedicated to them.

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1. All statements of fact, opinion, or analysis expressed are those of the author and do not reflect the official positions or views of the CIA or any other U.S. government agency. Nothing in its contents should be construed as asserting or implying U.S. government authentication of information or Agency endorsement of the author’s views. This material has been reviewed by the CIA to prevent the disclosure of classified information.

2. Parts of this book previously appeared in Matthew Kroenig, Exporting the Bomb: Why States Provide Sensitive Nuclear Assistance, American Political Science Review, Vol. 103, No. 1 (February 2009), pp. 113–133, reprinted with permission. For chapter 5, the final, definitive version of this paper has been published in Matthew Kroenig, Importing the Bomb: Sensitive Nuclear Assistance and Nuclear Proliferation, Journal of Conflict Resolution, Vol. 52, No. 2 (April 2009), pp. 161–180, by SAGE Publications Ltd., All rights reserved. ©. The article is available at http://jcr.sagepub.com/cgi/content/abstract/53/2/161.

Abbreviations and Acronyms

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INTRODUCTION

The Problem of Nuclear Assistance

Nuclear proliferation poses a grave threat to international peace and security. For this reason, politicians, policymakers, and academics worry that nuclear-capable states will provide sensitive nuclear assistance to other states or terrorist networks, further fueling the spread of nuclear weapons. For example, following North Korea’s nuclear test in October 2006, George W. Bush declared that the transfer of nuclear weapons or material by North Korea to states or non-state entities would be considered a grave threat to the United States, and we would hold North Korea fully accountable of the consequences of such action.¹

The empirical record provides reason for such concern. While states, to the best of our knowledge, have never provided sensitive nuclear assistance to terrorists, they have repeatedly transferred sensitive nuclear materials and technology to other states. From 1959 to 1965, France provided Israel with sensitive nuclear assistance; a mere two years after the end of French assistance, Israel is believed to have constructed its first nuclear weapon. This story, about one state helping another to develop nuclear weapons, is neither unique nor confined to the distant past. China assisted Pakistan with its nuclear program in the early 1980s with a package that included uranium enrichment technology, weapons-grade uranium, and a nuclear weapon design. Shortly thereafter, Pakistan is believed to have assembled its first nuclear bomb. More recently, from 1987 to 2002, Pakistan, with the help of Pakistani nuclear scientist A. Q. Khan, distributed sensitive nuclear technology and materials to Iran, Libya, and North Korea.² Since the end of this cooperation in 2002, Libya has agreed to give up its nuclear program, but North Korea has already tested its first nuclear device, and Iran is making steady progress on its own nuclear capability. These are a few of the many important cases of sensitive nuclear assistance that have contributed to the proliferation of nuclear weapons.

Yet, there is significant variation in the patterns of sensitive nuclear assistance. While some nuclear-capable states repeatedly provide sensitive nuclear assistance, many others refrain from transferring sensitive nuclear materials and technology altogether. Indeed, it is puzzling that states would transfer materials and technology that could help other states acquire nuclear weapons, the world’s most destructive weapons, weapons that could one day threaten the suppliers’ very existence.

This raises an interesting question about the motivations of the nuclear suppliers: Why do states provide sensitive nuclear assistance to nonnuclear weapon states, contributing to the international spread of nuclear weapons? This is the central question that this book will address. By sensitive nuclear assistance, I mean the transfer of nuclear materials and technologies directly relevant to a nuclear weapons program. This includes nuclear weapon designs, weapons-grade fissile material, and sensitive nuclear fuel-cycle facilities. This definition distinguishes sensitive nuclear assistance from civilian nuclear cooperation related to basic nuclear science and technology or the production of nuclear energy.

Despite the obvious real-world importance of sensitive nuclear assistance, international relations scholars have not yet addressed this topic. Academic analysts have explained why states want nuclear weapons, why states transfer conventional arms, and the effect of nuclear proliferation on the probability of war and crisis behavior but have not carefully examined the supply side of nuclear proliferation.³

Media reports and policy analyses of specific cases of sensitive nuclear assistance tend to assume that nuclear transfers are driven by economic considerations. Analysts claim that states in dire economic circumstances export sensitive nuclear materials and technology—and ignore the potential security risk—because they are in search of much-needed hard currency.

This book challenges this conventional wisdom. States that provide sensitive nuclear assistance understand the strategic consequences of their behavior quite well. In fact, state decisions to provide sensitive nuclear assistance are the result of a coherent, strategic logic.

The strategic theory of nuclear proliferation presented in this book is derived from a simple insight that is grounded in the nuclear deterrence literature: the spread of nuclear weapons threatens powerful states more than it threatens weak states.

Power-projecting states, states with the ability to project conventional military power over a particular target state, have a lot to lose when that target state acquires nuclear weapons. In interactions with a nonnuclear weapon state, power-projecting states can use their conventional military power to their advantage; they can threaten, or promise to protect, that particular state. Once that state acquires nuclear weapons, however, this strategic advantage is certainly placed at risk and may be fully lost. For these reasons, power-projecting states fear nuclear proliferation to both allied and enemy states. While the threat of nuclear proliferation is greatest when nuclear weapons are acquired by enemy states, nuclear proliferation, even to friendly states, can cause many problems for power-projecting states. Leaders in power-projecting states are concerned that nuclear proliferation will deter them from using military force to secure their interests, reduce the effectiveness of their coercive diplomacy, trigger regional instability that could engulf them in conventional conflict, weaken the integrity of their alliance structures, dissipate their strategic attention, and set off further nuclear proliferation within their spheres of influence.

On the other hand, non-power-projecting states, states that lack the ability to project power over a particular target state, do not incur these strategic costs when that target state acquires nuclear weapons. This is again true whether nuclear weapons spread to allied or enemy states. Non-power-projecting states are too weak to threaten hostile states and too weak to promise protection to friendly states, so they do not lose these strategic advantages as nuclear weapons spread. Because they lack the benefits afforded by a viable military option, the spread of nuclear weapons does not further undermine their strategic position. Their relative weakness precludes them from using military force to secure their interests, using military coercion as a tool of diplomacy, intervening in regional crises, extending security guarantees as a means to cement their alliance structures, needing to monitor new nuclear states, or needing to worry about further nuclear proliferation beyond their limited spheres of influence. Of course, non-power-projecting states may have other reasons to fear nuclear proliferation, but unlike for power-projecting states, the spread of nuclear weapons does not serve to constrain their conventional military freedom of action. For this reason, non-power-projecting states are on average less threatened by nuclear proliferation.

From this basic insight, this book derives three hypotheses about the conditions under which states will be more or less likely to provide sensitive nuclear assistance. First, because nuclear proliferation constrains states’ conventional military freedom of action, the better able a state is to project power over a potential nuclear recipient, the less likely it is to provide sensitive nuclear assistance. States do not wish to constrain themselves. Second, precisely because nuclear proliferation constrains power-projecting states, states are more likely to provide sensitive nuclear assistance to states with which they share a common enemy. By providing sensitive nuclear assistance to these states, a nuclear supplier can impose particularly high strategic costs on powerful rivals. Finally, because superpowers, states with global, force-projection capabilities, are threatened by nuclear proliferation anywhere in the international system, they pressure other states in an attempt to dissuade sensitive nuclear transfers. States that are vulnerable to superpower pressure are less likely to provide sensitive nuclear assistance.

In short, states provide sensitive nuclear assistance for strategic reasons. They are more likely to export sensitive nuclear materials and technology when it would have the effect of constraining an enemy and less likely to do it when it would threaten themselves.

Alternative explanations cannot account for the patterns of sensitive nuclear transfers. Economic explanations may be intuitively appealing, but I will show that they are not met with empirical support. There is no discernable relationship between a country’s economic circumstances and the likelihood that it will provide sensitive nuclear assistance. This is not to say that economic motivations are irrelevant to state decisions to transfer sensitive nuclear materials and technology. In some cases in which sensitive nuclear transfers occurred, the nuclear suppliers sought some form of payment. What the findings of this book make clear, however, is that states are unlikely to pursue economic gains when the result undermines their own security. States may still seek financial benefits when they export sensitive nuclear technology, but they are only likely to do so when such behavior is consistent with an underlying strategic logic.

Theories rooted in beliefs about the power of international institutions or related explanations about international norms cannot provide a satisfactory explanation for the causes of sensitive nuclear assistance. My finding is that the institutions of the nuclear nonproliferation regime have not exerted a consistent constraining effect on the nuclear export behavior of member states. Moreover, I find no support for the existence of an international norm against nuclear proliferation that discourages states from transferring sensitive nuclear material and technology. This is not to say that the nuclear nonproliferation regime has not served its purpose, however. While the regime may have failed to constrain sensitive nuclear transfers, I provide evidence that the NPT has played a role in retarding the international spread of nuclear weapons.

An explanation that centers on nuclear weapons possession cannot account for the patterns of sensitive nuclear assistance either. Capable nuclear suppliers are states that have the ability to provide sensitive nuclear assistance. Capable nuclear suppliers include states that possess nuclear weapons, like France, Pakistan, and the United States, as well as states, such as Brazil, Germany, and Japan, that have mastered parts of the nuclear-fuel cycle but have not developed nuclear weapons themselves. Some have argued that nuclear weapon states should be particularly opposed to nuclear proliferation because they have an incentive to prevent other countries from gaining entry into the nuclear club. Applied to the problem of sensitive nuclear assistance, we may expect that nuclear weapon states will be less likely to provide sensitive nuclear assistance than capable nuclear suppliers that lack nuclear weapons themselves. The evidence does not support this argument. Nuclear weapon states frequently help other states acquire nuclear weapons.

This book examines the consequences, as well as the causes, of sensitive nuclear assistance. When sensitive nuclear assistance occurs, what results? What is the relationship between sensitive nuclear assistance and the spread of nuclear weapons? I show that sensitive nuclear assistance is a powerful cause of nuclear proliferation. States that import sensitive nuclear materials and technology are more likely to acquire nuclear weapons than are similar states that do not receive outside help. Assistance from a more advanced nuclear state can help potential nuclear proliferators overcome the common technical and strategic hurdles they face as they attempt to develop nuclear weapons. The strong relationship between sensitive nuclear assistance and nuclear proliferation holds even after other factors thought to contribute to nuclear proliferation, such as living in a dangerous neighborhood with other nuclear-armed states or industrial capacity, are taken into account. This means that explaining sensitive nuclear assistance is a necessary first step if we hope to get a handle on how and why nuclear weapons spread. The key contribution of this book, therefore, is in providing empirical evidence for the first theoretical explanation of sensitive nuclear assistance.

I also address several other important issues in international relations theory and nuclear nonproliferation policy. First, I present a new, supply-side approach to understanding the causes of nuclear proliferation. The existing scholarship on nuclear proliferation has paid overwhelming attention to the demand side of nuclear proliferation. Explaining why states want nuclear weapons is important, but it is only part of the proliferation picture. After all, whether or not states want nuclear weapons is often immaterial, because other states take actions designed to assist or impede them. At one extreme, as we shall see, states are willing to provide sensitive nuclear assistance to help additional states acquire nuclear weapons. At the other extreme, states are willing to apply tough measures, including the use of military force, to stop the spread of nuclear weapons. If we are to understand the causes of nuclear proliferation, it is necessary to understand this supply side of nuclear proliferation. I examine the specific problem of sensitive nuclear transfers. Further research could examine other supply-side actions that states take to assist or impede nuclear proliferation in other states, such as voting on nuclear nonproliferation measures in international bodies, applying sanctions against nuclear proliferators, and supporting the use of military force against other states’ nuclear programs.

Second, I provide an original understanding of the consequences of nuclear proliferation. The literature on nuclear proliferation effects has long been dominated by the debate between proliferation optimists and proliferation pessimists.⁴ Proliferation optimists argue that, when it comes to the spread of nuclear weapons, more may be better because nuclear weapons increase the cost of conflict, deterring leaders from engaging in war against nuclear-armed states.⁵ The spread of nuclear weapons, in the optimists’ conception, has a pacifying effect on international politics, leading to international stability. On the other hand, proliferation pessimists argue that more will be worse because more nuclear weapons in the hands of more states increases the chance of preventive wars, crisis instability, and accidental nuclear detonation.⁶ According to the pessimists, nuclear proliferation contributes to greater levels of international instability.

The optimism/pessimism debate has done much to illuminate our understanding of the consequences of the spread of nuclear weapons. The existing scholarship, however, has been preoccupied with the study of the system-level effects of nuclear proliferation. In particular, these scholars have examined whether nuclear proliferation increases or decreases the stability of the international system. For this reason, the existing scholarship has devoted less attention to unit-level effects. In other words, both optimists and pessimists focus on how nuclear proliferation affects the world, but not on how it affects the individual states that inhabit that world. Scholars have, of course, examined how nuclear proliferation will affect the nuclear proliferators themselves, but they have not systematically examined how nuclear proliferation in one state will affect other states.⁷ Instead, the overarching concern of the optimism/pessimism debate has been to explain the relationship between nuclear proliferation and international stability. Due to this systemic focus, optimists and pessimists do not examine whether nuclear proliferation may affect different types of states differently. For instance, Waltz and Sagan tangle over whether the spread of nuclear weapons is good or bad, but they never seriously consider whether nuclear proliferation may be good for some states and bad for others.

In a significant departure from existing approaches, this book proposes a theory of nuclear proliferation that examines the unit-level, as well as the differential, effects of nuclear proliferation. It argues that nuclear proliferation threatens some states more than others and that the threat posed by nuclear proliferation depends on a state’s ability to project military power. This book shows that power-projecting states are threatened by nuclear proliferation primarily because the spread of nuclear weapons constrains their conventional military freedom of action. On the other hand, states that lack a power-projection capability are less threatened by nuclear proliferation and, under certain circumstances, can even benefit from it. Pessimists argue that the spread of nuclear weapons is bad, optimists argue that it may be good—I put forward the argument that it depends: the spread of nuclear weapons is bad for power-projecting states and may be good for non-power-projecting states.

It is of course the case that many small powers have historically opposed nuclear proliferation, and weak states may have other reasons to fear the international spread of nuclear weapons. These facts do not directly challenge the central point. While powerful states’ opposition to nuclear proliferation is determined by their strategic environment, the very different structural position of weak states provides them with greater freedom to oppose, or sometimes even support, the diffusion of nuclear weapons.

This novel approach promises to reinvigorate the study of the consequences of nuclear proliferation by establishing a research agenda on the differential effects of nuclear proliferation. Future research can identify the factors, other than power projection, that shape the degree to which states will be threatened by the spread of nuclear weapons.

Finally, the argument I propose has important implications for nuclear nonproliferation policy. In his 2009 annual report to Congress on the projected threats to the national security of the United States of America, Director of National Intelligence Dennis C. Blair assessed that the possibility of nuclear proliferation in various countries poses a great threat to U.S. national security.⁸ This was not a new recognition. Nuclear proliferation has been considered one of the top threats to U.S. national security for decades. In response to the continuing threat of nuclear proliferation, the United States has implemented a number of policies designed to stop states from transferring sensitive nuclear materials and technology. The effective execution of these and other nonproliferation policies requires an accurate assessment of which states are most likely to export sensitive nuclear materials and technology. Correctly understanding the conditions under which states provide sensitive nuclear assistance matters not simply for academic analysts of nuclear proliferation, but also for those who wish to prevent nuclear proliferation in the future.

Plan of the Book

This book is divided into six chapters. The next chapter, chapter 1, presents the central argument of the book. It examines the differential effects of nuclear proliferation and spells out their implications for the problem of sensitive nuclear assistance. The chapter explains how the spread of nuclear weapons disproportionately threatens power-projecting states, leading to three strategic conditions under which states are most likely to export sensitive nuclear materials and technologies. The chapter also develops competing explanations of sensitive nuclear assistance that will be tested against the power-based theory.

Chapters 2 through 5 constitute the empirical core of the book. Chapter 2 presents statistical results that reveal the correlates of sensitive nuclear assistance. The statistical analysis draws on an original sensitive nuclear assistance dataset. The dataset contains yearly information for all capable nuclear suppliers and potential nuclear recipients in the international system from 1951 to 2000.

In chapters 3 and 4, I use pattern-matching and process-tracing methods to examine the causal logic of the argument. Chapter 3 compares French assistance to Israel’s nuclear weapons program from 1959 to 1965 with U.S. efforts to thwart Israel’s nuclear development in the same time period. Chapter 4 tests the limits of the argument through an examination of several brief case studies. This chapter considers additional cases of sensitive nuclear assistance, as well as cases in which sensitive nuclear assistance could have occurred, but did not.

Chapter 5 assesses the consequences of sensitive nuclear assistance. Does sensitive nuclear assistance lead to nuclear proliferation? Drawing on case studies and quantitative analysis, this chapter demonstrates that states that receive sensitive nuclear assistance are more likely to acquire nuclear weapons than are similar states that do not receive outside help.

The conclusion provides a review of the argument and turns to the implications of the findings for theory and practice. The main thrust of the conclusion focuses on the implications of the argument for international relations theory. This analysis advances important scholarly debates on both the causes and the consequences of nuclear proliferation. The conclusion finishes with a discussion of the applications of the argument to U.S. nonproliferation policy. It considers the states that are at risk of becoming the next nuclear suppliers and explores whether they will provide sensitive nuclear assistance to rogue states or terrorist networks.

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1. President Bush’s Statement on North Korea Nuclear Test, October 9, 2006.

2. Pakistani assistance to Iran, Libya, and North Korea from 1987 to 2002 was state-sponsored by any reasonable definition of the term. As we will see in chapter 4, senior government officials, including heads of state and chiefs of army staff, actively supported the policy of nuclear transfer. See, for example, Gordon Corera, Shopping for Bombs (Oxford: Oxford University Press, 2006).

3. On state demand for nuclear weapons, see, for example, Scott D. Sagan, Why Do States Build Nuclear Weapons? International Security, Vol. 21, No. 3 (Winter 1996/97), pp. 54–86. On conventional arms transfers, see, for example, Andrew J. Pierre,