One other thing: any moron who cares to romanticize the SDS radicals of the 60s and 70s needs to take another look. During the civil rights movement in the 60s people were getting killed. schools and churches were bombed, and the human dignity of a race of people was at stake. The issues were pretty clear. (Nor should anyone start just blaming the South--remember the riots in Boston when the schools were integrated?)
It was very different later on, during the Vietnam war, when mass tantrums erupted on college campuses (it is much more fun to "demonstrate" than to study). When what mattered was what was cool and what wasn't--and if protesting was cool to a suburban American teenager, violence was even more so. Because we didn't know what it was really like.
I lived in Nyack New York when my kids were little, and I was walking down South Broadway to the fish store, across the street from the Police station, when all hell broke loose; sirens sounded, police cars came from everywhere and began disgorging enraged policemen who were kicking and literally punching a man through the door into the police station; a man with long hair and a beard. It was the day of the Brinks robbery, and these were the high-principled souls who had just shot a cop who tried to prevent them from robbing a Brinks truck. The whole town felt vulnerable all of a sudden--and not safe, not really ever safe again. The funeral parlor was across the street from my apartment building, and the streets were full of Nyack residents holding lit candles. Everyone, everyone was sad. Next day the policeman was given a full inspector's funeral.
My friend drove the schoolbus his little 5 year old son rode every day. Just the one passenger on that route--this little kid who lost his father.
Those radicals--they weren't principled, they weren't idealists--they were evil. Nasty, brutal, and privileged. They came from relatively affluent families (I'm sure their fathers made more money than the policeman they killed) and were well able to live their lives completely divorced from reality.
I've met radicals from other countries, countries with really bad governments-- and very few of them have any respect for Americans who dabble in radical politics--because we really dont' know what the hell we are talking about. I doubt if even now many left-wingers would recognize real tyranny if they had to live under it.