Before Zinn was a historian, he was a U.S. Air Force bombardier who dropped bombs on people Czechoslovakia, Hungary, Germany and France during World War II, and was involved in some of the first military uses of Napalm.

The experience left him with lingering questions regarding the ultimate justice of that “good war”, and such critical self-reflection led him to study history under the G.I. Bill.

As a professor of history, he went on to radicalize the students at Spellman College on the eve of the explosion of the Civil Rights Movement, wrote the first book arguing for immediate U.S. withdrawal from Vietnam, and helped Daniel Ellsberg hide the Pentegon Papers.

He was even part of a diplomatic effort to North Vietnam during the war, and helped secure the release of some U.S. POWs. While there he witnessed the effects of U.S. cluster bombs on Vietnamese toddlers.

He then spent the rest of his long life writing and teaching history, including the best introductory history of the United States ever written.

I always associate Zinn with that other great writer who died recently, Kurt Vonnegut. Although Zinn writes history and Vonnegut writes fiction, the work of both were animated in large part by their experiences in World War II. They both played a role at the military edge of the American Empire at its historic “best” – during its fight against fascism – but came away with deep misgivings about the whole enterprise, which required a personal evolution beyond nationalist patriotism and towards a more universal concern that made their books so radical and so valuable.

(He died hours before Obama’s first State of the Union address, but not before giving his own assessment of the President’s performance so far.)