From listening to many suicidal and rageful/violent people and hearing information similar to what we are beginning to learn about Loughner, I believe that four factors may have contributed to his actions.
We don't know all the facts from Tuscon, Arizona yet, but we do know that every single day, 34 Americans die to gun violence. And so it will continue until we get serious about cracking down on illegal guns and protecting innocent people.
Pundits in the aftermath of the Tuscan shooting are failing to address the reforms that could prevent these incidents in the first place. What's needed is reform of our involuntary commitment and treatment laws.