One interesting data point in all such insane public shooting sprees in the US AFAIR is that the perp was on psychiatric medication. That includes this latest Connecticut case where the Lanza guy is reported to have "a history of mental illness". In the US, "mental illness" records include such things as any kind of depression, attentiveness problems, addictions, or anything you've popped a pill for.
Its become a strangely unimaginative culture when the solution to human sadness or slack is a pill.
My psychiatrist friends all admit that most of their patients' problems would easily be resolved by the gradual learning and practice of simple "life skills". Yet, they admit they just prescribe pills and patients prefer it that way because of "no time". They acknowledge that many such patients become psychologically addicted to such medical quick fixes for anything from the blues to attentiveness problems, etc. They also admit that "everything has side effects", but are more reluctant to speculate on whether the cumulative effect of these side effects eventually causes serious neuro-biological imbalances.
The interesting thing about these shooting incidents is that there is a coordinated campaign against the 2nd amendment as if on cue, but not a peep about the culture of insanity behind it, and the role of the psychiatric drugs industry in it.
"The society prepares the crime and the criminal commits it". Someone had posted this news report from China on the same day -
China school knife attack in Henan injures 22 children. Would one have to ban knives too? This is one of several such incidents in China in recent times.
The bottom line is that insanity cannot be handled by making or abolishing laws. That's not quite mature, to say the least. It can only be handled by teaching people the responsibility that comes with owning and handling weapons to protect one's fellow-citizens who abide by certain values. And those high values are enshrined in the same US Constitution.
IMHO, just like "sex education", the school system should incorporate a "weapons education" program to give citizens the required hatting to bear arms - hatting in terms of moral code and sense of responsibility, pride, camaraderie and national values.