While politicians in Washington deal in abstractions, supposing the passage of more laws will somehow constrain the behavior of law-hating criminals, those who live in the real world see a more trustworthy avenue -- allow teachers to be armed.
St. Louis Police Chief Tim Fitch is pushing for this in his city because he understands that the ultimate check on criminal behavior is the threat of immediate repercussions which could prove fatal to the perpetrator.
As I've written previously, allowing the possession of weapons by teachers who have concealed carry permits or who have met legal requirements for carrying in states that don't require permits, is simply common sense. But whenever this idea is floated, politicians who live in the abstract and teachers unions are quick to say schools aren't the place for guns.
Police Chief Fitch answers this objection by pointing out that a lot people think airplanes aren't the place for guns either, yet we frequently fly in planes where pilots are armed with handguns (whether we know it or not).
Pilots have been armed now for many, many years, [and because of it] we've not had another hijacking and the issue is, for the bad guy, he doesn't know which airplane he's getting on, if the pilot is armed or not.
And this is how it would work in schools, where teachers would keep concealed weapons on their persons in such a way that criminals would not know which teachers in which schools were carrying and which weren't. It would force the criminal to assume most teachers in most schools are carrying, and they'd have to find a new soft target for their crimes.
Passing more laws will never accomplish this, because criminals, by their very nature, have zero fear of the law. They do, however, still have some degree of fear of immediate retribution.