The lessons of Sept 11th are not that we should fear terrorism, or that we should give up freedoms for security. The lessons of Sept 11th are that we should help where we can, never take our loved ones for granted, appreciate our gifts and our freedoms, and live every day as if it were our last.
The people who went to work in the Towers that morning thought they would come home that evening. Many of them probably bolted through their morning routines. They might have remembered to kiss the spouse and kids, but they might not. If they could have chosen where to spend their last breaths, I doubt many would have chosen the office.
The firefighters, the police officers, the everyday folks who pitched in and helped, who ran toward danger rather than away from it, were showing us the way. That we give of ourselves, as much as we can, to help others.
Terrorism can strike anywhere, even the heart of New York City. America is not immune. But you can't protect against a truly determined killer willing to sacrifice himself; all we can do is try to get at the root cause, and not make more terrorists.