Remember that the 9/11 attack was only partially successful. Now they can't use commercial airliners to finish the job because we're prepared for that this time. If we were smart, we'd be looking to head them off from their next attack instead of preparing for 9/11 to happen again.

Finish what job? Hitting the U.S. Capitol with Congress in session. That's part of it, obviously. You say you want to attack civilian planes. Well, that can be done too. Just crash a cargo plane into an airport taxiway with 20 planes waiting to take off.

Why are cargo planes attractive? Because the terrorists would control the timing. They wouldn't be the mercy of airline schedules. The next attack has to be perfectly timed before defenses can be launched, a compete surprise, then it's over in seconds.

They don't have to hijack cargo planes. They can use money. That's why are so attractive. They have more cash than we are willing to admit.