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.
http://en.wikipedia.org/wiki/My_Lai_M…
Calleys apology YouTube video
https://www.youtube.com/watch?v=LPHEv…

Project Camelot Channel
http://projectcamelot.info