By Sharon Cohen — The Rev. Martin Luther King Jr. marching arm-in-arm with other civil rights activists. Cesar Chavez hoisting a picket sign in a farm workers’ strike. Gloria Steinem rallying other feminists for equal rights. During the 1960s and into the 1970s, amid the turbulence of protests for civil rights and against the Vietnam War, every movement seemed to have a famous face — someone at a podium or at the front of a march who possessed a charismatic style, soaring oratory and an inspiring message.