Because the generation that was being sent into the fight didn't understand why we were fighting in a country halfway around the world, and because they didn't agree with the way we treated people in our own country
Woodstock came from this, as a way to spread ideas about this and other things people wanted to change.
He was referring to a Democratic Government, and the expectations for citizens were that no matter what social class men were in, they were required to serve the country, and make political decisions