The sixth edition of "American National Security" has been extensively rewritten to take into account the significant changes in national security policy in the past decade. Thorough revisions reflect a new strategic context and the challenges and opportunities faced by the United States in the early twenty-first century. Highlights include: an examination of the current international environment and new factors affecting U.S. national security policy making; a discussion of the Department of Homeland Security and changes in the intelligence community; a survey of intelligence and national security, with special focus on security needs post-9/11; a review of economic security, diplomacy, terrorism, conventional warfare, counterinsurgency, military intervention, and nuclear deterrence in the changed international setting; an update of security issues in East Asia, South and Southeast Asia, the Middle East, Sub-Saharan Africa, Russia and Central Asia, and Latin America and the Caribbean; and, new material on globalization, transnational actors, and human security.