Forgive me for repeating my comments from other thread where you shared this.

Jim, I'll be interested in reading what the Commission says. Maybe it could have been prevented if Ben Laden had been killed or Al Qaeda had been hit harder earlier or if the intelligence services were more like they are in James Bond movies (sorry, trying to lighten the mood). Again, all I said is that Clarke admitted that all the things he recommended combined wouldn't have prevented 9/11.

That doesn't mean it couldn't have been prevented at all, though I suspect we'll discover that it could have been prevented in the same way that Pearl Harbor could have been prevented. If you knew the attack was possible and put up torpedo nets, if the handful of patrol planes had been sent in the right direction instead of ordered south by staff in Washington, if the people manning the new radar sets had properly interpreted their data, and so on. Before Pearl Harbor only a few people in the world believed you could sail aircraft carriers that far and use planes to attack with torpedoes in the shallow harbor. Unfortunately they were Japanese or Americans to low it the military pecking order to have much say. Top brass didn't believe it possible, and it wasn't by the old rules. The attack changed the world and made the new rules obvious in retrospect. In that case, the Top Brass were made scapegoats despite the fact that they were getting contradictory orders and information from all side, all the way up the chain of command. Being obvious in retrospect is very different from being obvious before the fact, of course, so eventually the Top Brass at Pearl were vindicated and the final responsibility shared.

Before 9/11 only a few people had considered using planes as missles...