'Columbine,' by Dave Cullen -- New York Magazine Book Review
“Eric Harris and Dylan Klebold did not go on a killing spree because they were picked on, or because they were pagans, or because Colorado had lax gun laws. Eric was a cunning, calculating psychopath who wanted to kill as many people as possible, and Dylan was a depressive who wanted to kill himself. That is it.”
I thought it was because of rock music and video games!