J. Samuel (“Sam”) Walker is the former historian of the U.S. Nuclear Regulatory Commission and the author of Prompt and Utter Destruction: Truman and the Use of Atomic Bombs against Japan. He is also the author of five books on the history of regulating nuclear power, including Three Mile Island: A Nuclear Crisis in Historical Perspective and The Road to Yucca Mountain: The Development of Radioactive Waste Policy in the United States.