This young guy who committed this heinous act was suffering from one or more symptoms of paranoid disillusioned schizophrenia.
Enhanced no less with the fearful distrust and hatred toward government officials as well as the police, who busted him once for drug possession.
Being rejected as an applicant to join the US military could have also heighten his hatred toward the government as a whole.
The recent and apparent emotional distrust posed against the people who are holding positions in government right now just stoked up
his off balanced fragile emotional state. How the US federal government has been putting money out to corrupt corporations and doing little for the
poorer working class has caused some to go off the deep end emotionally.
I agree with what Simon stated though on the easy accessibility of guns in certain areas of the States. How is a gun shop owner to know if
the person in his store is emotionally unstable and positioning himself to commit harm to others ? The point is where there are gun shops,
there are going to be emotionally off balanced people willfully wanting to buy guns with intent to harm others. Where there are no gun shops
with flashing neon signs in the window, you wont find these things happening.