I entirely understand your predicament, we sometimes run into crazies on the road and there really is nothing we can do and sometimes law enforcement can do nothing to help us.

My dad one time ran into a drunk guy in a car who pulled a gun on him after he tried to door him.

Sometimes the best thing is to count your blessings and if you really want to pursue actions against him try looking up the city he is from (If that is even possible).

Sorry to hear about that.