A compelling biography of John Foster Dulles, one of the most complex and underexamined architects of US foreign policy. John Foster Dulles is a towering yet misunderstood figure in American and international history. Best known as secretary of state under Dwight D. Eisenhower and as the namesake for the Dulles airport, he has long been cast as a Cold War hardliner—moralizing, rigid, and ready to meet Soviet threats with nuclear force. Yet this view, while enduring, leaves much of his intellectual legacy unexplored. In John Foster Dulles, Bevan Sewell presents a compelling intellectual biography that restores Dulles as a central architect of the American-led world order in the twentieth century. Across a remarkable career that spanned the Versailles Peace Conference, landmark legal work on international finance, leadership in Christian ecumenical movements, and his representation of the United States to the nascent United Nations, Dulles consistently sought to shape a global system anchored by American values in a transnational context. His was a vision of peace not as passive coexistence but as a dynamic, evolving framework of moral, economic, and political order. Far from the caricature of an inflexible ideologue, Dulles emerges as a thinker attuned to the complexities of change. His philosophical pragmatism, informed by religious conviction and diplomatic experience, guided a lifelong search for durable solutions to global conflict—even as it exposed glaring contradictions in his policies. Dulles's work was rooted in empire, inspired by a belief in American exceptionalism, and constrained by the biases of his time. Based on wide-ranging research and a sharp reassessment of Dulles's intellectual development, Sewell reframes the legacy of John Foster Dulles for a new generation and offers a substantial and novel interpretation of his influence on US foreign relations in the twentieth century.