Nuclear Dialogues examines how a discursive process constructed the nuclear nonproliferation norm in international relations. Zoë I. Levornik’s innovative new study traces the evolution of the norm from the dawn of the nuclear age to the present day and how it emerged and diffused through the actions of antinuclear activists and members of the antinuclear movement. Antinuclear activists did not only protest nuclear weapons, but used discursive action to (re)construct the meaning of nuclear weapons. The invention of the atomic bomb led to debates over its “true” nature and utility. It was a dispute between two counternarratives, one that sought to normalize nuclear weapons as just “bigger bombs” and one that fought to delegitimize them. Antinuclear activists won the war of words and succeeded in establishing a dominant antinuclear discourse, which shaped how we perceive and think about these weapons today. Controlling the discourse was the first step in establishing the norm; the second was shaping public opinion and influencing nuclear policy. Antinuclear activists leveraged public opinion to pressure decisionmakers to enter into arms control and disarmament treaties, which helped institutionalize the norm politically and even legally. Few studies have connected the dots between the nonproliferation norm, nuclear policies, and the challenges they sometimes faced. Nuclear Dialogues contains important lessons on the power of discursive arguments to shape policies and perceptions, change words, and change the world.