[W]hat's more important is that thousands of students attend college who struggle with depression and other mental illnesses, and almost all of them hurt no one and deserve to stay there. Identifying the Cho-type exceptions before they explode is a matter of good campus police work and counseling, not harsh, interventionist crackdowns.
This is an argument for increased empahsis on gun control efforts, in my view. Controlling the supply of guns is much more straight-forward than trying to predict whether bio-chemical imbalances will lead one to commit violent acts. Even in this day and age, none of us can read another person's mind. It would be a shame if school authorities overreacted--thereby creating an even greater stigma around mental illness--while trying.