Excerpts from Books and Wikipedia
"The US troops, under the command of Lieutenant William Calley, were sent to root out Vietcong guerrillas and their sympathizers, believed to be hiding in the village of My Lai. The slaughter that followed was unprovoked and indiscriminate, resulting in the massacre of old men, women, and children. . . . Such an atrocity as My Lai was hardly surprising, and the horrifying news, when it finally broke, would galvanize and unify the antiwar US movement." [Furtado: 1001 Days]