AN AMAZING phenomenon, predicted by no one, occurred in America in the late 1980s and early 1990s. The world was experiencing what Charles Krauthammer calls the greatest democratic awakening in human history, a rush to democracy inspired by America. That, in turn, was accompanied by the collapse of communism, the dismantling of the Soviet empire, and the resurgence of capitalism, each the result of decades of American effort. At home there was a communications revolution and an entrepreneur-led economic boom that produced the most sustained period of peacetime prosperity in American history. These were extraordinary developments but hardly inexplicable. The amazing thing was what followed. America went neurotic, growing gloomy and pessimistic, fearful of the future, embarrassed by the recent past. Hard to figure.