In another meeting, Eisenhower argued that nuclear war was not a real option, and thus widespread, serious planning for it was a waste of time and money. It wasn’t merely a matter of building better weapons or deeper shelters if a nuclear conflict came: “There just aren’t enough bulldozers to scrape the bodies off the street.”

For his part, Lyndon Johnson lived in fear of the button. “When Richard Nixon took the oath,” Johnson recounted, “the greatest burden lifted from me that I have ever carried in my life.” He explained, “Never a day went by that I wasn’t frightened or scared that I might be the man that started World War III.”