A book version of the essay that sparked a great debate on both sides of the Atlantic in 2002. In this tour de force, Kagan argues that today's conflict between the United States and Europe is not simply a result of passing policy disputes or the Bush administration's foreign policy style. Rather, it reflects a more profound estrangement rooted in American power and European weakness. The old Atlantic partners live today on different planets. America's preeminent global position has thrust it into a Hobbesian world of lurking threats and made it more willing to use force, whereas Europe seeks peace through law and diplomacy. Kagan is best in describing Europe's postwar project of taming the dangers and instabilities of power politics in a democratic, Kantian zone of peace. Thanks partly to the U.S. security guarantee, Europeans have devised a political order in which power is subdued and the use of force banished. Yet Europe has also made itself weak, Kagan charges, as its nations remain unable to confront the anarchical dangers of the wider world. Kagan argues that America's realpolitik view is not only a feature of Republican administrations but a deeper expression of American power (after all, Bill Clinton was willing to bomb Iraq, Afghanistan, and Sudan). The result is a growing divergence in strategic views and eroding solidarity.
Kagan's characterization of a postmodern Europe, however, is too German-centered; he ignores the fact that the United Kingdom and France retain great-power identities and a willingness to use military force. His reading of the United States is also debatable. The United States has been the preeminent global power since World War II, yet it has often pursued its national interest through multilateral institutions and security partnerships. Pace Kagan, Europe and the United States might disagree on the nature of threats outside the West -- as they have in the past -- but their own relationship remains embedded in an Atlantic security community.