Dr. Martin Luther King, Jr. famously came out against the Vietnam War before he was assassinated in April 1968. And, http://www.commondreams.org/views03/0120-03.htm "> according to David Garrow, King's Pulitzer Prize-winning biographer, if King were alive today at age 75, he'd be spending almost every waking hour organizing mass demonstrations against the US occupation of Iraq.
From 1961 to 1966, King somehow found the time to write an annual essay for The Nation on the state of civil rights and race relations in America. Click here to read "Let Justice Roll Down," from the March 15, 1965 issue of the magazine.
Also read King's inspiring Declaration of Independence from the War in Vietnam, delivered at Manhattan's Riverside Church in April of 1967. It's unfortunately still very timely.