Sorry, didn't have all the details when I wrote my reply so I left it out. I tend to forget book titles and authors these days...

It's called "The Doomsday Machine: Confessions of a Nuclear War Planner" by Daniel Ellsberg, the guy who leaked the Pentagon Papers (which describe the US' involvement in the Vietnam War and how it was much more extensive and violent than they had been telling the public, including bombing Cambodia and Laos, and which helped turn public opinion against the war). Ellsberg worked with the DoD on national security and with the RAND Corporation on US nuclear strategy.