The My Lai massacre took place in March of 1968 right at the tail end of the Tet offensive. In one respect it was a microcosm of everything that was wrong with the United States involvement in the Vietnam war.
It’s a gut wrenching story and some would say that justice has never been done because very little prison time was served by those who participated, encouraged, or covered it up – thanks to Nixon who gave Calley a get out of jail free card after only a couple of months prison time.
Here’s some related links.
Calleys apology YouTube video
Project Camelot Channel