At the close of the Cold War, much of the world was concerned that America, with its instinct for isolationism, would express satisfaction with global victory, gather up its men and equipment and head back across the oceans to the testudinal safety of its homeland. Some welcomed the prospect: the Chinese, for example, looked forward to a lot more elbow-room in Asia. The French were also heartened by the promise of a less pervasive America, seeing the opportunity for reasserting French primacy in Europe, an instinct induced by both nostalgia and self-delusion.

But most of the world, it seemed, didn’t much like the idea of American withdrawal. The British, those consummate players of the Washington game, suddenly became fidgety at the table. It looked as if they were about to lose their ace in the hole. Others feared that America, as the sole remaining superpower, would abandon the world to its own disorder.

This did not happen. Across the American political spectrum it was largely agreed that the era of isolationism was dead. What did happen, however, was that the United States, for all its considerable military and economic muscle, had little idea what