This book has entertained one of most interesting theoretical puzzles and serious policy issues today: why have so few states acquired nuclear weapons? To address the question, I have argued that we need to examine states’ social environments as well as security environments. If the international social environment created and supported by the NPT exerts influence on elite perceptions and decisions, then the security environment cannot be understood without understanding the social environment. This proposition led to two main insights. First, not all nuclear forbearance is alike. Some state elites may be persuaded, others may be constrained by social conformity, and still others may identify with important allies. Second, it is important to identify and understand the mechanisms through which the social environment exerts influence.
These issues are examined through in-depth analysis of Japan and Egypt and briefer assessments of Libya, Sweden, and Germany. While these case studies provide a great deal of insight, more countries need to be studied to confirm or counter findings categorically. However, some conclusions can be drawn. All five of these countries faced inhospitable security environments, and yet all ended up exercising nuclear forbearance. Their decision-makers did this not because of adequate security substitutes for nuclear weapons (although these helped), but because they redefined state goals in such a way as to devalue nuclear weapons. Without the norms and denial policies embedded in the nuclear nonproliferation regime, Egypt and Libya would have acquired a nuclear option, and Japan, Germany, and Sweden might have done so as well. But while the NPT and associated agreements were an important factor in these states’ nuclear forbearance, they were not the only cause of leaders’ redefinition of security and success, and this is a critical topic for further study.
For all five states, the shock of humiliating defeat in war may have jumpstarted this transformation of state interests. This is not likely the cause, however, in states such as South Africa, Argentina, Australia, Switzerland, and numerous other countries that once had nuclear weapons programs. Nevertheless, the international social environment created powerful forces to guide state decision-makers into making a public commitment against nuclear