This Article explores the development of the Clean Air Act of 1963, the first law to allow the federal government to fight air pollution rather than study it. The Article focuses on the postwar years (1945-1963) and explores the rise of public health medical research, cooperative federalism, and the desire to harness the powers of the federal government for domestic social improvement, as key precursors to environmental law. It examines the origins of the idea that the federal government should “do something” about air pollution, and how that idea was translated, through drafting, lobbying, politicking, hearings, debate, influence, and votes, into a new commitment to a national program to end air pollution in the United States. In addition to presenting new perspectives on this understudied period in the development of environmental law, it is hoped that this work will shed some light on the nature of political opposition to environmental regulation, which today is one of the greatest challenges to effective pollution control.