In 2009 William L. Calley, the only U.S. Army officer convicted of the 1968 slaying of Vietnamese civilians at My Lai, made an extraordinary public apology.
Calley was a young Army lieutenant when he was court-martialed for his part in the massacre of 500 men, women, and children. In his confession he said, “There’s not a day that goes by that I do not feel remorse for what happened t...