Howard Zinn, author of ''A People's History of the United States, '' tells his personal stories about more than thirty years of fighting for social change, from teaching at Spelman College to recent protests against war. A former bombardier in WWII, Zinn emerged in the civil rights movement as a powerful voice for justice. Although he's a fierce critic, he gives us reason to hope that by learning from history and engaging politically, we can make a difference in the world.