Edward Fishman, a former Treasury official who worked on sanctions policy, tells the story of how the United States turned economic networks into weapons. He traces the development of financial warfare from targeted sanctions against individual terrorists to comprehensive campaigns against entire national economies. The book examines major cases: the campaign against Iran's nuclear program, the response to Russia's invasion of Ukraine, the growing confrontation with China. Fishman provides insider perspective on how sanctions are designed, implemented, and enforced, including the technical details of how money moves and how those movements can be blocked. He assesses both successes and failures, examining when sanctions achieve their goals and when they impose costs without changing behavior. The book addresses concerns about overuse: as the U.S. weaponizes the dollar, other countries seek alternatives, potentially undermining the very infrastructure that makes sanctions possible. For readers interested in American power, foreign policy, or international finance, Fishman provides essential analysis.