Well put. My observation was based on the subtle (?) connection between the words of the zombie marine rescuer on revenge and the epilouge of his serving in Iraq is uncharacteristic of Stone. This is a conclusion that I found a kindred spirit with in the following review:
Notice the words of Michael Koresky: "The mini-narrative of Dave Karnes (Michael Shannon, in a performance so wooden, ethereal, and divorced from the rest of the film, it’s seems likely to have been shot by a second-unit director), the business-man who immediately quits his day job, goes to church (the cross is seen in gigantic close-up onscreen), shaves his head, and dons full marine regalia before discovering and rescuing John and Will from the rubble, seems designed only to provide Stone with a thoroughly counterintuitive move. “It’s going to take a lot of good men to avenge this,” he says; there’s no hint of irony here, even when at the close of the film a title card announces that this nearly anonymous hero served two tours of duty in Iraq. It’s a conclusion that plays right into the misconceived, if highly successful, ideological connection between 9/11 and the current Iraq debacle." [full review found here.] http://reverseshot.com/article/strong_world_trade_center_strong
The Karne's character was nearly a distraction from the drama of the film. He was a caricature more than a person. When asked for a shorter version of his name, indicating his personal name sans military title, he says "Staff Sergeant". That was absolutely the U.S. version of the same sort of idealistic, self suppression that the Islamic nutjobs show in thier fighting. The difference is his was the religion of nationalism and thiers is the religion of religious craziness.
Again, I thought it was an entertaining movie. It could have been about a kid trapped in a mine and it would have been the same story, people coming together for a common goal.