ABSTRACT
This chapter examines the history and rationales for US-European security cooperation, the role of 9/11 in altering threat perceptions on both sides of the Atlantic, and some possible future paths for the transatlantic partnership. It focuses on the nature and process of alliance politics, and argues that the relationship must be considered in terms of power and the role of interests, rather than ideas and norms, as key determinants of state behavior. The key to understanding recent tensions in US-European relations is the changes in the relative power capabilities of states. The end of the Cold War left the international system in turbulence, where the missions and futures of institutions that tied the Atlantic together were themselves in an uncertain state of flux. The fact that the most vociferous opposition to the war on Iraq came from member North Atlantic Treaty Organization (NATO) allies in Europe is a portent for the future of US-European relations.
