The disintegration of the Soviet Union heralded the most significant transformation in global politics since World War II, a turning point that was destined to have a profound impact on a system which, until recently, was considered by many to be relatively stable. Forces that guided relations between East and West dissolved as the collapse of a superpower produced a new environment where opportunities for conflict and cooperation became less clearly defined.
Although the significance of this transformation is widely recognized, consensus breaks down on the precise implications for nuclear proliferation, nuclear deterrence, and superpower crisis management. Should the decline and fall of the Soviet Union provoke optimistic or pessimistic forecasts about global peace and security as we approach the twenty-first century? Will the shift away from "power bipolarity" create a more stable or a more hostile nuclear environment? Are these changes likely to intensify or diminish the horizontal proliferation of nuclear weapons in the Middle East and other parts of the developing world? If proliferation intensifies, will changes in the Cold War balance affect escalation and management of military-security crises between nuclear states in the next decade? In sum, will we come to miss the relative stability of the "long postwar peace" ( Gaddis 1986, 1987, 1991; Mearsheimer 1990a,b,c; Kegley 1991) or welcome the relative security of the "New World Order," with the United States occupying the sole superpower role? Providing answers to these questions is an important challenge to international relations (IR) scholarship today.