I know, all this is true, but
I really don't care if the guy was in a friggin' hot air balloon. You simply cannot let someone, who may be criminal, may be terrorist, or may simply be crazy, highjack any form of aerial transport and fly around for hours above your financial center and densely populated urban area.
I still say, "Blast 'em out of the sky!"
It also sends a very strong, positive message to all the little jihadis training in their Al Queda camps in Pakistan, or elsewhere. They'll sit up and take notice, and think, "Hmmm, maybe we better not try that method of attacking the infidels..."