I'd like to repeat what's been said already in here, the guns he used were stolen. So, the only way this could have been stopped would be for her to be unable to legally get a gun because her son is crazy, right? So if you have anyone in the house who might be a little weird, then you don't have the right to get a gun for personal safety?
It's actually not that difficult. This guy's neighbors had sensed something off about him for years, but there was no way for them to report this--what could the police do? What could the state do? Maybe if we gave more attention to improving mental health facilities, and gave more power to the state to act on reports from family members or neighbors of disturbed and potentially dangerous people, we'd see fewer incidents like this. In other words, if I feel my neighbor might be unstable, I should be able to report that to state authorities, who would then examine my claim, see if it has any worth, and if it does, they should have the power to assess the person in question, and if the person is found to be a potential danger to others, the state should have the power to require that the person be treated and/or committed.
So, the only way this could have been stopped would be for her to be unable to legally get a gun because her son is crazy, right?
Actually, yes, something like this. Not necessarily prevent her from buying guns (though in this case, that probably would've been advisable, given what is coming to light about her personality), but there should be more monitoring. In other words, if someone in your household has issues with violence or certain mental illness, you basically ought to have to submit to some form of periodic monitoring or evaluation. So, maybe once a year, or twice a year, you'd have to submit psychiatric health evaluations of the mentally ill person in your household to the state in order to be allowed to retain your gun license. And if you have such a person in your household, you need to have a state inspector come visit your house once a year to ensure that you keep your guns in a safe place, or in a gun locker at a shooting club. I don't think that's a lot to ask, and I don't think most people would be against it.
Was he on record for being violent? If not, then how does the government draw the line?
As a matter of fact, the individual in this case had had trouble with the law numerous times in his life due to his mental conditions, but the nature of these incidents is confidential on account of him being a minor at the time. So it's not like he was entirely unknown to law enforcement, but again... the state is afforded very little power in such cases. He should have been required to see a psychiatrist every
x months, and if found to be potentially dangerous, committed to a mental health facility.
Edit-Also, with a **** like this, do you think he'd go "oh well I don't have guns so I'll use a knife"? Really?
A guy in China did it almost exactly at the same time this happened:
http://www.cnn.com/2012/12/14/world/asia/china-knife-attack/index.html
The guy, who of course was mentally ill, attacked 22 primary school children with a knife. The difference between what happened in China with a knife and what happened in the US with a gun? The former resulted in 22 wounded children who all survived. The latter resulted in over two dozen fatalities.
Another thing to keep in mind: the shooter attempted to purchase guns not long before the incident, but was denied because he was under 21. And if his mother hadn't kept a bunch of guns easily available at home for her unstable son to take (and she knew full well he was unstable, and so did others; new reports are surfacing that she'd expressed concerns about her son. Moreover, the guy caused enough concern at school that he'd had a psychologist assigned to him), this very well could have been avoided.
In other words, this was a breakdown on several levels: gun laws, mental health laws/facilities, and personal/civic responsibility. The mother should either not have been allowed to purchase firearms, or she should have had to go through much more stringent assessment and background checks and licensing/education. On top of that, the school/state/authorities should have had the power to commit the guy to an institution, given his history and given the concerns of the people around him.