Nuclear Weapons and Non-proliferation: Is Restraint Sustainable?

Predictions of nuclear proliferation since the 1950s have proven to be almost wholly unreliable. Not only has the widely held expectation that the international system would be populated by a 'nuclear-armed crowd' failed to come to pass, the degree of restraint exercised by nuclear-capable states has undermined one of the most powerful tenets of realist international relations theory-that states in an anarchic international system will inevitably opt for the most powerful military capabilities they are able to acquire. A range of factors account for proliferation restraint, including the norms promoted by the non-proliferation regime, the role of extended deterrence, and a genuine moral aversion to nuclear weapons on the part of national leaders. One of the key policy related questions of our time is whether this restraint is sustainable in the twenty-first century. This article challenges some of the alarmist predictions about proliferation and argues that the disincentives for states acquiring nuclear weapons will remain robust in spite of the dramatic expansion of nuclear energy worldwide and the difficulties confronting the non-proliferation regime.