This is the definitive account of the ideas, politics, and diplomacy that went into the historic decision to expand NATO to Central and Eastern Europe. Drawing on the still-classified archives of the U.S. Department of State, Ronald D. Asmus recounts how and why American policymakers, against formidable odds at home and abroad, expanded NATO as part of a broader strategy to overcome Europe's Cold War divide and to modernize the alliance for a new era.