It is almost standard to introduce an argument on US national security policy by emphasizing the changes in the international system since 1989. While the significance of these changes cannot be denied it is important to remember that systemic influences on a state’s national security policy are limited. Indeed one can argue, as Alexander Wendt has done, that the system is what the powerful states make of it. For most of the Cold War the policy of containing the Soviet ideological and military threat united realist and idealist around a common cause. Even then events like the Hungarian uprising in 1956, the Vietnam War, the Reagan doctrine and the collapse of the Warsaw Pact often exposed the tension in the realist advocacy of order without the pursuit of democracy and the liberal belief that promoting democracy should be primary aim of US foreign policy. The chapter focuses on how these persistent dilemmas have found expression in Bush and Clinton presidencies.