Howard tells that story in the film and I tell it at greater length in my memoir

Howard tells that story in the film and I tell it at greater length in my memoir, Secrets: A Memoir of Vietnam and the Pentagon Papers (pp.376-81). But for reasons of space, I had to cut out the next section in which Howard–who had been arrested in DC after most of the rest of us had gone elsewhere–came back to Boston for a rally and a blockade of the Federal Building. I’ve never published that story, so here it is, an out-take from my manuscript:

A day later, Howard Zinn was the last speaker at a large rally in Boston Common. I was at the back of a huge crowd, listening to him over loudspeakers. 27 years later, I can remember some things he said. “On Mayday in Washington thousands of us were arrested for disturbing the peace. But there is no peace. We were really arrested because we were disturbing the war.”

He said, “If Thomas Jefferson and Alexander Hamilton had been walking the streets of Georgetown yesterday, they would have been arrested. Arrested for being young.”

At the end of his comments he said, “I want to speak now to some of the members of this audience, the plainclothes policemen among us, the military intelligence agents who are assigned to do surveillance. You are taking the part of secret police, spying on your fellow Americans. You should not be doing what you are doing. You should rethink it, and stop. You do not have to carry out orders that go against the grain of what it means to be an American.”