How have the weapons of the nuclear age changed the rules of international politics? Can co-operation replace coercion as an instrument of security? This book compares the biographies of four dissident intellectuals who grappled with these questions throughout their careers - Louise Weiss, Leo Szilard, E.P. Thompson, and Danilo Dolci. Though they shared a revulsion for the balance of terror, they possessed sharply divergent visions of a post-Cold War peace, from the Gandhi-like non-violence of Dolci to Szilard’s relentless quest for US-Soviet joint diplomacy. Weiss, a French journalist and realpolitiker, believed that a united European military power would break the Cold War impasse; Szilard, a physicist and father of the atomic bomb, pressed for co-operative diplomacy between the superpowers; Thompson, a British historian, mobilized millions in the grassroots campaign for European Nuclear Disarmament; and Dolci, an Italian poet, experimented with conflict resolution through education and non-violence. By comparing the ideals, successes, and failures of these activists, this book illustrates the problematic boundary between realism and utopianism in the nuclear age.