Good Question: What Makes A Mass Murderer?

MINNEAPOLIS (WCCO) -- Anders Breivik is far from the only person in Norway, in the world, with anti-immigrant, anti-Muslim views. There are those who fantasize about carrying out a violent attack, but virtually none of them do. So how does someone with extreme opinions become someone carrying out extreme violence?

"We need to be careful to remember that this isn't a snap. This is very deliberate, very well thought out," said Dr. Mike Thompson, a forensic psychologist in Minneapolis. Thompson has spent decades evaluating criminals with severe psychological disorders.

"The first place we want to go: This has to be the work of someone who's mentally ill, somebody who has serious problems," Thompson said. "No doubt he did."

According to Thompson, however, the research on "lone wolves" who go from having extreme views to taking action doesn't show a trend of psychotic mental illness.

While stressing that he doesn't know Breivik and therefore certainly is in no position to be diagnosing, he said, "I doubt this person is what we would call psychotic, where he clearly lost connection with reality. But he's so enmeshed with his own thinking."

Breivik wrote a 1,500-page manifesto, telling his life story and sharing his views, which sounded similar to those of the Unabomber, Ted Kaczynski.

"Kaczynski was threatened by technology, and this gentleman was threatened by multiculturalism," Thompson said.

In fact, Breivik plagiarized Kaczynski's manifesto. Kaczynski wrote: "One of the most widespread manifestations of the craziness of our world is leftism." Breivik took out the word "leftism," and put in "multiculturalism."

"He was so absorbed by his beliefs and the rightness of his beliefs, and so narcissicistic that he honestly thought he could start a revolution," Thompson said.

Monday Breivik said that there were other cells in the terrorist network to which he belonged.