The European Union has always had a role in “soft security” by anchoring stability on the European continent through integration and enlargement. In recent years, it has moved to harness the military capacity of its member states through the European Security and Defense Policy (ESDP) to project stability in and around Europe—and perhaps beyond. There are conflicting views of the future of EDSP and its implications for transatlantic relations. On the one hand, ESDP and its related goals are, in part, the result of American pressures on Europeans to improve their military capabilities and share greater burdens with the Alliance. On the other hand, there is concern in some quarters in the United States about more autonomous European planning and decision-making. After the September 11 terrorist attacks, significant questions have arisen on both sides of the Atlantic about divergences in American and European strategic outlooks and the implications for European and transatlantic institutions. While some Americans are focused on further military transformation, many Europeans are advancing important changes on their own continent. The EU is central to those changes, but it faces choices about how to manifest its security vocation. This book examines how the evolution of the European Union’s strategic presence is likely to affect transatlantic debates, and what it could mean for the EU’s role as an actor in international security.