Book excerpt: A foreign policy expert “presents a thoughtful, comprehensive case” for the War on Terror—a “historically powerful support of Mr. Bush and his doctrine” (Washington Times). The terrorist attacks of September 11, 2001, shattered the tranquil and prosperous optimism that had blossomed in the United States during the 1990s. President George W. Bush responded with a preemptive Global War on Terror. This controversial strategy led the nation into protracted conflicts in Iraq and Afghanistan and ignited passionate debate about America’s role in the world. In Defense of the Bush Doctrine offers a vigorous argument for the principles of moral democratic realism that inspired the Bush administration's policy. Conservative columnist Robert G. Kaufman argues that the purpose of American foreign policy is to ensure the integrity and vitality of a free society and that America’s grand strategy must be guided by the cardinal virtue of prudence. Kaufman provides a broad historical context for America’s post-9/11 foreign policy, connecting the Bush Doctrine and other issues, such as how the United States should deal with China, to the deeper tradition of American diplomacy. Drawing from positive lessons as well as cautionary tales from the past, Kaufman concludes that moral democratic realism offers the most prudent framework for expanding the democratic zone of peace and minimizing threats to the United States.