It turns out that Daniel Ellsberg, who stole and released the Pentagon Papers, stole and planned to release a lot of information on U.S. nuclear weapons.

It turns out that Ellsberg also took many thousands of pages of documents pertaining to another subject: nuclear war. Ellsberg, a prominent thinker in the field of decision theory, had worked on the military’s “mutual assured destruction” strategy during the Cold War. Once a believer in deterrence, he now says he was a collaborator in an “insane plan” for “retaliatory genocide.” He wanted to tell the world decades ago; with nuclear threat looming again, he’s put the whole story into a new book, The Doomsday Machine…

Ellsberg believed that his bureaucratic opponents — mainly the military brass — were not thinking through the consequences of nuclear war. Then, in 1961, he was allowed to see a piece of information previously unknown even to Kennedy, the death count the military projected for theoretical strikes: some 600 million, not including any Americans killed in counterattacks. (That was still an underestimate.) Ellsberg writes of being gripped with a feeling of revulsion, realizing that the document “depicted evil beyond any human project ever.” The planners weren’t heedless — they intended to inflict maximal civilian casualties. “The shock was to realize that the Joint Chiefs knew,” Ellsberg tells me. “I was working for people who were crazier than I had thought. I had thought that they had inadvertently constructed a doomsday machine, without knowing it…”

The book examines many close brushes with nuclear war. He says that at least twice during the Cold War — once aboard a Soviet submarine during the Cuban Missile Crisis, once inside an air defense bunker outside Moscow in 1983 — a single individual came close to triggering a nuclear war because of a false alarm. “There is a chance that somebody will be a circuit breaker,” Ellsberg says. “What I conclude is that we’re lucky, very lucky.”