I'm more interested in the total lack of air cover over the Pentagon on 9/11, almost an hour after the towers were attacked.
Testicles should roll over that one, IMO that was incompetence of the highest order.
The other stuff...
Well you could blow up a passenger liner out of Miami, or plant a few dozen of those tiny anti-personnel mines in Central Park for starters, the only real limit is the imagination of the bad guys.
Trying to defend against that is not easy.