Bernie was a paranoid nut job looking for someone to shoot
I don't think he was paranoid at all.
At the time of the shooting, the New York Subway was one of the most violent places on Earth.
If you entered the subways in NY at that point in time without a firearm,you were basically signing your own death warrant.
His trigger finger may have been a little bit itchy, but not to the level of "paranoia."
When I was in college during that era. a college friend of mine lived in the neighborhood of Queens. When he went home from college, he always had his boys at the Port Authority so he would stand a chance fighting his way from Times Square to his home.