I’ve been a freelancer for much of my career. In 1969, I broke the story of a unit of American soldiers in Vietnam who had committed a horrific war crime. They were ordered to attack an ordinary peasant village where, as a few officers knew, they would get no opposition—and told to kill on sight. The boys murdered, raped and mutilated for hours, with no enemy to be found. The crime was covered up at the top of the military chain of command for eighteen months—until I uncovered it.