Ever since it became clear that an exhausted Soviet Union was calling off the Cold War, the quest has been on for a new American role in the world. Roles, however, are not invented in the abstract; they are a response to a perceived world structure. Accordingly, thinking about post-Cold War American foreign policy has been framed by several conventionally accepted assumptions about the shape of the post-Cold War environment.
First, it has been assumed that the old bipolar world would beget a multipolar world with power dispersed to new centers in Japan, Germany (and/or "Europe"), China and a diminished Soviet Union/Russia. Second, that the domestic American consensus for an internationalist foreign policy, a consensus radically weakened by the experience in Vietnam, would substantially be restored now that policies and debates inspired by "an inordinate fear of communism" could be safely retired. Third, that in the new post-Soviet strategic environment the threat of war would be dramatically diminished.
All three of these assumptions are mistaken. The immediate post-Cold War world is not multipolar. It is unipolar. The center of world power is the unchallenged superpower, the United States, attended by its Western allies. Second, the internationalist consensus is under renewed assault. The assault this time comes not only from the usual pockets of post-Vietnam liberal isolationism (e.g., the churches) but from a resurgence of 1930s-style conservative isolationism. And third, the emergence of a new strategic environment, marked by the rise of small aggressive states armed with weapons of mass destruction and possessing the means to deliver them (what might be called Weapon States), makes the coming decades a time of heightened, not diminished, threat of war.
The most striking feature of the post-Cold War world is its unipolarity. No doubt, multipolarity will come in time. In perhaps another generation or so there will be great powers coequal with the United States, and the world will, in structure, resemble the pre-World War I era. But we are not