Kyle said 'I love killing bad guys - even with the pain I loved what I was doing.'
The most disturbing passage in the book to me was the one where Kyle talked about being competitive with other snipers, and how when one in particular began to threaten his "legendary" number, Kyle "all of the sudden" seemed to have "every stinkin' bad guy in the city running across my scope."
After reading the above quotes from excerpts of his book, and then when he couldn't kill anymore in Iraq he came home and made up stories about killing people here. Someone doesn't do that unless they enjoy killing. I'm sure some of what he did was because he believed he was saving U.S.soldiers. But his #1 reason for being there, and going back over and over was because he enjoyed killing people.