I'd personally demand political changes to be made to fix the problem, but who cares what I think here in Sweden
There are many roots of the problem and I do think they have been identified. The solutions go something like this:
* Decrease poverty.
* Decrease alienation of the poor.
* Lessen the availability of guns.
I'm convinced of that acting on any of those will lessen the problem. The two first are related, but giving convicted criminals the right to vote would be a good first step. Having affordable and good state sponsored schools on all levels is another one of those fairly cheap ways to raise the poor out of hopelessness. Removing the guns is of course by far the cheapest solution, but not the least complicated and is a very very long term solution.
But USA is very rich which no doubt is the result of having such little aid to the poor. Being poor in USA only sucks slightly less than being poor in the jungles of Africa. They have plenty of reasons to work hard as hell. And they do and USA is rich, so there is obviously a positive pay off.
The important thing to reconcile is that USA has the high-school shootings they do and the high prevalence of murder because that is what the voters have chosen. US voters want this society. They obviously think the heightened chance of getting their kids mowed down in school is a price worth paying for their wealth and right to bear arms. They might not have reasoned just like this on their way to the voting booths, but this is the choice they made.
...and then we've got crazy people. Crazy people without guns are just as crazy as crazy people with guns, the difference is that they can't shoot anybody. But mental care is an extremely expensive solution to this problem.
It's a complex issue with many solutions, and all the solutions costs money and freedoms. The question is simply if you think the price is worth paying?