He's listing them in order of the time as it builds up. I forgot the name, but it starts with a "C".
The My Lai massacre changed public perception of Vietnam drastically. Many people already thought it was an unjust war, and this added to that anti-war sentiment. When many veterans came home they were treated like trash, because everyone back home saw the terrible war crimes committed by the U.S. Many people called for an end to Vietnam after it.
It was based on shipping finished goods
