The Cold War is over and the international system is in a state of flux. The threat of superpower nuclear war has receded and has been replaced by new and more diffuse threats about the stability of the post-Cold War world order. Among the many changes in the post-Cold War psychological context, two in particular stand out: the absence of an external enemy and the shifting nature of domestic constraints on foreign policy. This chapter examines these changes and their implications for American foreign policy. The post-Cold War world is still taking shape, and there is only fragmentary evidence on which to base an analysis. Powerful enemies allow leaders to mobilize populations in support of domestic goals. The general reluctance of the American people and their elected representatives to support military intervention in Europe, Africa, and the Caribbean is in the first instance attributable to the end of the Cold War and the collapse of the Soviet Union.