The point of departure in this assessment of nuclear hedging and latency is why and how numerous states that embarked on the path of developing nuclear weapons, or at least seriously toyed with the idea, never ultimately acquired them. By some estimates there seem to have been in total roughly 30 such states, approximately 20 by some other experts’ accounts.1 Regardless which of these estimates one adopts, it is clear that at the end of the day only a small fraction of those have crossed or even come close to the finish line.2 Why is this the case? What explains the considerable contrast between the number of states that embarked on the nuclear-weapon path and those that ended up with nuclear weapons? This chapter is a further effort to look systematically at the nuclear hedging phenomenon in the early 2000s.3
1 The most salient works, cited in my original paper, that estimate 20 states include T. V. Paul, Power versus Prudence: Why Nations Forgo Nuclear Weapons (Montreal: McGill-Queen’s University Press, 2000); Mitchell Reiss, Bridled Ambition: Why Countries Constrain Their Nuclear Capabilities (Washington, DC: Woodrow Wilson Center Press, 1995). More recent analyses that suggest closer to 30 states are Philipp C. Bleek, “Does Proliferation Beget Proliferation? Why Nuclear Dominoes Rarely Fall” (Ph.D. diss., Georgetown University, 2010); Matthew Fuhrmann and Benjamin Tkach, “Almost Nuclear: Introducing the Nuclear Latency Dataset,” Conflict Management and Peace Science 32, no. 4 (2015): 443–61; and “Nuclear Weapons Programs Worldwide: An Historical Overview,” Institute for Science and International Security, http://isis-online.org/nuclear-weapons-programs.
2 The difference between the two set of estimates is only modestly explained by difference in data availability. It is mostly a function of employing different definitions (or benchmarks) for determining which countries are counted as nuclear weapon aspirants.
3 Ariel Levite, “Never Say Never Again: Nuclear Reversal Revisited,” International Security 27, no. 3 (Winter 2002/2003): 59–88.