Mr Red, I appreciate that the US couldn't have possibly done nothing, but revenge is most definitely not the only answer. The US could have made a lasting change to their foreign policies, they could have appointed people to figure out why someone would want to attack them in the first place, and then they could have changed their ways accordingly. the fact that there is still not even conclusive proof that it was osama bin laden who was behind the attacks strengthens the case against revenge even more.