This book boldly challenges conventional wisdom about the value of preventive war. Beginning with the rise of German power and the French and British response to the Rhineland crisis leading to World War II, Scott Silverstone overturns the common impulse to point an accusing finger at British leadership for its alleged naïveté, willful blindness, or outright cowardice. Arguing against the belief that Britain could have contained Germany and avoided war if it had used force when Hitler remilitarized the Rhineland, the author uses this dramatic event to wrestle with a general strategic problem that has broad relevance for our current foreign policy dilemmas. Silverstone argues that the Rhineland crisis is a critical case for studying a central dynamic of world history—power shifts among states—and the preventive war temptation that power shifts frequently produce. There has been surging interest in the idea of preventive war, an interest stimulated by the Bush administration's articulation of the "preemption doctrine" in 2002 and the disastrous invasion of Iraq in 2003, and by frustration over the difficulty of preventing the proliferation of nuclear weapons by such states as North Korea and Iran. Clarifying the way we think about preventive war, the author analyzes the enduring strategic flaws in preventive war that must inform how political leaders and the public think about this option as a means of dealing with shifting threats in the modern world. Offering a radically conservative argument for when to wage war, this persuasive book will be essential reading for policy makers and concerned citizens alike.