This movie has certainly tapped into a part of the Zeitgeist. Unfortunately, it's not a good part. Twenty years from now, I am certain that this movie will be the subject of many papers. After all, it's an apologetic for wiretapping, torture, and "good" people doing very bad things to stop a mad, chaotic terrorist.
This film offers no catharsis. The tension builds, but it never builds toward anything but more tension. On the whole, this was a two-and-a-half hour ordeal. I think the reason this movie is so well beloved can only be attributed to something like the Stockholm syndrome.