As of this writing, nobody has interviewed Nadal Malik Hasan, the Ft. Hood shooter. Nevertheless, I think I'll stick my neck out and make a prediction. From what I've heard and read so far, I suspect that Hasan had a lot more in common with Dylan Klebold and Eric Harris — the teenagers responsible for the 1999 shootings at Columbine High School — than with Mullah Omar or Abu Nidal.
An army post. A high school. In groups. Outsiders. Makes sense to me.