Joseph S. Nye in Project Syndicate:
What 9/11 illustrates is that terrorism is about psychology, not damage. Terrorism is like theatre. With their powerful military, Americans believe that “shock and awe” comes from massive bombardment. For terrorists, shock and awe comes from the drama more than the number of deaths caused by their attacks. Poisons might kill more people, but explosions get the visuals. The constant replay of the falling Twin Towers on the world’s television sets was Osama bin Laden’s coup.
Terrorism can also be compared to jujitsu, in which a weak adversary turns the power of a larger player against itself. While the 9/11 attacks killed several thousand Americans, the “endless wars” that the US subsequently launched killed many more. Indeed, the damage done by al-Qaeda pales in comparison to the damage America did to itself.
More here.