Dr. Martin Luther King Jr. and Rev. Ralph Abernathy, right, lead a march on behalf of striking Memphis sanitation workers March 28, 1968. The dignity of the march soon gave way to disorder as a group of about 200 youths began breaking windows and looting. King agonized over what had happened. Within a week, King was dead, killed by an assassin's bullet at Memphis' Lorraine Motel. (AP Photo/Sam Melhorn, The Commercial Appeal)