One, do not send in troops to do police work.
Two, as you said, identity troublemakers early, and send them packing.
Of course, both of these are easier said then done.
I witnessed riots on another campus during that timeframe. Many of the “students” were actually violent mentally challenged non-students. There were about 20 violent aggitators on a campus of 10,000.
The state troopers were undisciplined rednecks - a very dangerous situation. Property damage, but no major injuries.