Millions of Americans have read and been galvanized by A People's History of the United States. But many years before Howard Zinn published that epic saga of exploitation and resistance, he was organizing civil-rights protests and agitating for an end to the Vietnam War--and writing about those efforts in the pages of The Nation. From the Atlanta campus of Spelman College (where Zinn taught in the early 1960s) to North Vietnam (where he facilitated...