An interesting essay by Owen Harries, an Australian scholar who seems to have a pretty good grasp of what America is and what it's about. His conclusion is a bit sobering:

Let me be clear: After the outrage of September 11, I do not believe that the United States could have reacted in any way other than as she did. But doing so will carry a cost. The long term significance of what happened some months ago may be that it forced America decisively along a course of action that-by emphasising her military dominance, by requiring her to use her vast power conspicuously, by making restraint and moderation virtually impossible, and by making unilateralism an increasing feature of American behavior-is bound to generate widespread and increased criticism and hostility towards her. That may turn out to be the real tragedy of September 11.