FROM STRENGTH TO STRENGTH
More than a decade ago, political columnist Charles Krauthammer proclaimed in these pages the arrival of what he called a "unipolar moment," a period in which one superpower, the United States, stood clearly above the rest of the international community ("The Unipolar Moment," America and the World 1990/91). In the following years the Soviet Union collapsed, Russia's economic and military decline accelerated, and Japan stagnated, while the United States experienced the longest and one of the most vigorous economic expansions in its history. Yet toward the close of the century readers could find political scientist Samuel Huntington arguing here that unipolarity had already given way to a "uni-multipolar" structure, which in turn would soon become unambiguously multipolar ("The Lonely Superpower," March/April 1999). And despite the boasting rhetoric of American officials, Huntington was not alone in his views. Polls showed that more than 40 percent of Americans had come to agree that the United States was now merely one of several leading powers -- a number that had risen steadily for several years.
Why did the unipolarity argument seem less persuasive to many even as U.S. power appeared to grow? Largely because the goal posts were moved. Krauthammer's definition of unipolarity, as a system with only one pole, made sense in the immediate wake of a Cold War that had been so clearly shaped by the existence of two poles. People sensed intuitively that a world with no great power capable of sustaining a focused rivalry with the United States would be very different in important ways.
But a decade later what increasingly seemed salient was less the absence of a peer rival than the persistence of a number of problems in the world that Washington could not dispose of by itself. This was the context for Huntington's new definition of unipolarity, as a system with "one superpower, no significant major powers, and many minor powers." The dominant power in such a system, he argued, would be able to "