I found this web posting by Umar Farouk Abdulmutallab to be particularly revealing in thinking about what may have lead to his extremism.
“I have no one to speak too [sic],” read a posting from January 2005, when Umar Farouk Abdulmutallab was attending boarding school. “No one to consult, no one to support me and I feel depressed and lonely. I do not know what to do. And then I think this loneliness leads me to other problems.”