Institute, under the Department of Homeland Security, a Campus Marshal program similar to the Federal Air Marshal program.
Air Marshals provide a level of deterrence (they blend in with the passengers; a potential attacker must take into account the possibility of armed response). Campus Marshals would provide a similar level of deterrence in much the same way.
Air Marshals are the first (and final) line of defense for passengers against an attempted hijacking or other attack on board. Similarly, Campus Marshals would be the first line of defense for the student body against an attack.
Since they would blend in with the student body, an attacker would not be able to target them for early elimination.
Being on campus would significantly improve response time.