The quest of the European Union (EU) to develop capabilities in security and defense affairs has been a surprisingly contentious issue in transatlantic relations over the past decade. Officials in EU governments have been perplexed that European Security and Defense Policy (ESDP), which they see as integral to building the EU in all of its dimensions, is viewed in some American political circles with trepidation, or even as a grave threat to the North Atlantic Treaty Organization (NATO). Most Europeans believe that ESDP will actually strengthen the Alliance by allowing Europeans to assume a larger share of the burdens of transatlantic security. While Washington has long professed support in principle for ESDP, American objections to specific EU defense initiatives have led some European governments to doubt the strength of that support. However, European efforts to press the development of ESDP in the context of recent crises have heightened American concerns that the project is designed to displace rather than bolster NATO. Some of the controversy can be attributed to periodic rhetorical flourishes by European officials that greatly overstate near-term ESDP capabilities or long-term goals. Certain American concerns are due, in part, to misperceptions and misunderstanding of ESDP structure and activities on this side of the Atlantic. Michael Brenner's fluid and incisive analysis chronicles the development of ESDP and assesses its durability and driving political motivations. In the process, he helps to demystify the functioning of ESDP, which is of particular value to American readers unfamiliar with this initiative. Professor Brenner also advances a number of sound recommendations for U.S. policymakers about handling ESDP. As he argues, if Washington consults with European allies in ways that diminish concerns about American unilateralism, reduces restrictions on technology transfers critical to European defense modernization, and develops reliable modalities for NATO--EU military cooperation, then the prospects that ESDP will evolve in a manner consistent with long-term U.S. interests will greatly increase. This paper sheds much light on a European project whose outcome is critical to American security. Stephen J. Flanagan, Director Institute for National Strategic Studies