It'll keep happening so long as this country continues to ignore the well-being its own population.

It also still remains true that it's a very minor threat compared to many others that we face in our day-to-day lives. I'm not saying we shouldn't do anything about it. I'm saying that we should always be aware of the true scope of the problem, and prioritize various measures accordingly.

I suspect that the single biggest policy change that would drastically improve matters is universal healthcare, and particularly prophylactic treatment of mental health. It would also solve a lot of other problems. "Active shooter drills", on the other hand, create mental health problems without solving anything.