Why Do States Build Nuclear Weapons?: Three Models in Search of a Bomb

NuclearWeapons? Three Models in Search of a Bomb ! w h y do states build nuclear weapons? Having an accurate answer to this question is critically important both for predicting the long-term future of international security and for current foreign policy efforts to prevent the spread of nuclear weapons. Yet given the importance of this central proliferation puzzle, it is surprising how little sustained attention has been devoted to examining and comparing alternative answers. This lack of critical attention is not due to a lack of information: there is now a large literature on nuclear decision-making inside the states that have developed nuclear weapons and a smaller, but still significant, set of case studies of states’ decisions to refrain from developing nuclear weapons. Instead, the inattention appears to have been caused by the emergence of a near-consensus that the answer is obvious. Many U.S. policymakers and most international relations scholars have a clear and simple answer to the proliferation puzzle: states will seek to develop nuclear weapons when they face a significant military threat to their security that cannot be met through alternative means; if they do not face such threats, they will willingly remain non-nuclear states.’ Scott D. Sagan i s Associate Professor of Political Science and a faculty associate of the Center for lnternntional Security and Arms Control at Stanford Umrersit!/. I greatly benefited from discussions about earlier drafts of this article at seminars at the Aspen Strategy Group, the Institute for Defense Analysis, the Lawrence Livermore National Laboratory, the Monterey Institute of International Studies, the Olin Institute for Strategic Studies, and the Stockholm International Peace Research Institute. For especially detailed comments and criticisms, I thank Itty Abraham, Eric Amett, Michael Barletta, George Bunn, Colin Elman, Miriam Fendius Elman, Peter Feaver, Harald Miiller,George Perkovich,JessicaStern, and Bradley Thayer.Benjamin Olding and Nora Bensahel provided excellent research assistance. Support for this research was provided by the W. Alton Jones Foundation and the Institute for Defense Analysis. 1. Among policymakers, John Deutsch presents the most unadorned summary of the basic argument that “the fundamental motivation to seek a weapon is the perception that national security will be improved.” John M. Deutsch, ”The New Nuclear Threat,” Foreign Affairs, Vol. 71, No. 41 (Fall 1992), pp. 124-125. Also see George Shultz, ”Preventing the Proliferation of Nuclear Weapons ,” Department of State Bulletin, Vol. 84, No. 2093 (December 1984),pp. 17-21. For examples of the dominant paradigm among scholars, see Michael M. May, “Nuclear Weapons Supply and Demand,” American Scientist, Vol. 82, No. 6 (November-December 1994),pp. 526-537; Bradley A. Thayer, ”The Causes of Nuclear Proliferation and the Nonproliferation Regime,” Security Studies, Vol. 4, No. 3 (Spring 1995), pp. 463-519; Benjamin Frankel, “The Brooding Shadow: Systemic Incentives and Nuclear Weapons Proliferation,” and Richard K. Betts, ”Paranoids, Pygmies, Pariahs , and Nonproliferation Revisited,” both in Zachary s. Davis and Benjamin Frankel, eds. The Infernational Security, Vol. 21, No. 3 (Winter 1996/97),pp. 5446 0 1996 by the President and Fellows of Harvard College and the Massachusetts Institute of Technology 54 Why Do States Build Nuclear Weapons? I 55 The central purpose of this article is to challenge this conventional wisdom about nuclear proliferation. I argue that the consensus view, focusing on national security considerations as the cause of proliferation, is dangerously inadequate because nuclear weapons programs also serve other, more parochial and less obvious objectives. Nuclear weapons, like other weapons, are more than tools of national security; they are political objects of considerable importance in domestic debates and internal bureaucratic struggles and can also serve as international normative symbols of modernity and identity. The body of this article examines three alternative theoretical frameworkswhat I call "models" in the very informal sense of the term-about why states decide to build or refrain from developing nuclear weapons: "the security model," according to which states build nuclear weapons to increase national security against foreign threats, especially nuclear threats; "the domestic politics model," which envisions nuclear weapons as political tools used to advance parochial domestic and bureaucratic interests; and "the norms model," under which nuclear weapons decisions are made because weapons acquisition , or restraint in weapons development, provides...