The terrorist attacks of September 11, 2001, brought together two related but distinct phenomena. First, they presented the calling card of al Qaeda and more generally of militant Islam. These attacks were rightly perceived as an act of war by a group seeking to catalyze a political-religious movement. Much of America's effort since then has been to destroy that group, its sanctuaries, and its affiliates; some of the effort has been to counter the psychological, social, and political appeal of militant (predominantly Wahabi) Islam.