Bearcat, I would easily give you 500-1 odds on that hundred. It just won't ever happen. Seeing as there is only an infinitesimal chance that an airliner in the US could be taken over like on 9/11, and the very small chance that if one was that a fighter would be close enough to even intercept in time, the odds of an actual shootdown are effectively zero.

Small planes violate DC airspace on a fairly regular basis. Typically they're read the riot act by ATC, and they are told to land - unescorted - in Frederick or Manassas or sometimes just to continue on to their destination. Someone from the FBI comes out, someone from FAA, they're again read the riot act, and that's the immediate end of it. The FAA may ding them later, but they're not hauled off to jail or anything.