My idea to help reduce the risk of future shootings: We should have a law that would allow parents to be able to voluntarily admit their child to a mental hospital up until age 25. Currently parents can keep their child on their insurance until this age, but upon the 18th birthday, the child becomes an "adult" and parents no longer have control.
Unfortunately, mental disease in male adolescents tends to bloom in the later teens. The usual pattern I have observed is that the parent will start getting the child some mental help: first with some counseling, then perhaps with a psychiatrist and medications. Both plans are tempered by the incorrect perception that mental hospitals are awful places and the treatment of last resort. Parents anguish over the concept of "committing" their child to a hospital, and with that backdrop, the outpatient therapy seem to be appropriate at the time for the severity of the mental disease the child is displaying. Unfortunately, adolescents tend to hold in a lot of their thoughts and getting to know how they are thinking is a long, slow process when carved into weekly one hour sessions. Soon, the boy turns 18 and the mental disease has been progressive but now the parents have NO ABILITY TO GET HIM HELP unless he wishes to get help. Often as mental disease progresses the perception to the patient himself that help is needed diminishes and this, together with the reality that the child perceived that the previous therapy wasn’t actually helpful or even unpleasant, leads to the (now adult in the eyes of the law) child to drop out of treatment entirely. If he is not felt to be an immediate danger to himself or others he doesn't meet criteria for involuntary hospitalization. If he was younger, the parents would be able, easily, to get him admitted to a facility to try to diffuse the situation and get him the help and safety he needs.
This plan would be ideal on many levels, and, I believe, would have no realistic opposition. Since the admission to the facility would only take place under the same conditions as if he were under 18: that a psychiatrist believes an inpatient admission could benefit him, there is no way of parents using this punitively, etc.
Our boys age, and with that aging comes a loss of resilience to the stressors they face. The guns they have access to is only a part of the battle. The reality is the war is one of mental disease, and we need a new, national strategy to combat this, as our current laws and systems, CLEARLY, has not.