India and Pakistan’s nuclear detonations in May 1998 underscored the post-Cold War risk of regional arms races in weapons of mass destruction. The danger of nuclear weapons spread is aggravated by the spread of delivery systems, including ballistic missiles, capable of delivering nuclear and other WMD over thousands of kilometers. The U.S. supremacy in high-technology, conventional military power tempts aspiring regional hegemons to acquire nuclear weapons as deterrents against possible deployment of U.S. and allied forces into hostile theaters of war. 1 The potential for nuclear leakage from already weaponized states into the hands of frustrated state and nonstate actors is considerable and, in some cases, already documented.
Despite these trends, some highly regarded scholars have minimized the risk of nuclear proliferation or even argued that, under certain controlled or fortuitous conditions, the spread of nuclear weapons would improve stability. The same perspective on proliferation also raises important issues about how theory in international relations can predict or explain policy. The optimists about proliferation follow the logic of models that explain and predict well for conventional war and deterrence, but not for a more nuclearized world.
In the following discussion, we first consider the assumptions of political realism on which many arguments dismissive of the risks of nuclear weapons spread are based. Second, we argue that the assumptions and logic of political realism lead to some important wrong inferences about the relationship between nuclear weapons and peace during the Cold War and,