Reading the article, you see a depressed young man with few friends -- exactly the type of person targeted by terrorist/Muslim groups as a possible dupe. Using Americans to destroy this country gives them the greatest satisfaction.
He's pretty much the same personality profile they had for Johnny Walker Lindh, the shoe bomber, and for that matter Tim McVeigh.
A well-connected, popular guy is NOT going to go blow up a stadium of families for his Pakistani roomie.