We've spent the past several decades tearing apart the country, the family, and the community. We've taken God (however you want to define Him) out of the public life, we've embraced an "anything goes" culture that promotes actions without consequences, that mocks traditional and family values, that doesn't teach personal responsibility, and that says there's no place in a civil society for talk of absolute rights and wrongs - instead it's your wrong is my right, everything is relative, etc.....and we're then shocked when that society acts in ways that are pure evil.
We've embraced everything in this country that cheapens and destroys life - abortion and infanticide of our children, euthanasia and assisted suicide of our handicap and elderly, the death penalty for our imprisoned. We have an entertainment industry that thinks its job is to "push the limits" of indecency that is broadcast to our children, and then we buy our children violent video games and music that celebrate and glamorize pornography, drugs, and murder.
Guns are not the problem. It is the culture that we have created which is the problem.
There's also an excellent (short) read from the director of the Mental Illness Policy Org discussing steps to take to deal with and care for our mentally disabled. Most importantly is refocusing our efforts and resources on the small number that are truly a danger to themselves and the community. http://www.nationalreview.com/corner/335767/five-point-action-plan-president-obama-reduce-violence-mentally-ill-d-j-jaffe