What makes for war or for a stable international system? Are there general principles that should govern foreign policy? This book explores how historical work can throw light on these questions. The essays in this book deal with specific problems—with such matters as nuclear strategy and U.S.–European relations. But the book's main goal is to show how in practice a certain type of scholarly work can be done. The book demonstrates how, in studying international politics, the conceptual and empirical sides of the analysis can be made to connect with each other, and how historical, theoretical, and even policy issues can be tied together in an intellectually respectable way. These essays address a wide variety of topics, from theoretical and policy issues, such as the question of preventive war and the problem of international order, to more historical subjects—for example, American policy on Eastern Europe in 1945 and Franco-American relations during the Nixon–Pompidou period. But in each case, the aim is to show how a theoretical perspective can be brought to bear on the analysis of historical issues, and how historical analysis can shed light on basic conceptual problems.