"More proof of the stupidity of the whole thing is the US sending F16s after Cessna 150s. What are they going to do if they catch one? Shoot it down? Imagine the collateral damage on the ground! Despite the fact that a light airplane has never been used in a terrorist attack and even if it was to be so used, it would be almost completely ineffective?"
A Cessna filled with sarin wouldn't be effective? A cessna flown in to a crowd in a concert wouldn't be effective? A cessna filled with a hundred pounds of HE flown into a building wouldn't be effective? The explosives that killed all those in the double decker in London was by accounts carried in a back pack sized item. You don't have to kill thousands to be an effective terrorist, just enough to hold the attention of the public and press.
I'd rather not be around to find out if your beliefs in the stupidity of a C152 being deadly have any merit.