Most of the hijacking at the time of the rule change was done by fruitcakes wanting a trip to Cuba, in the 70's we saw the first instance of well organized groups which resulted in much loss of life and aircraft.

Times changed before the ink was really dry, and it turned out that the tactics were wrong right out of the gate and it took decades to fix, but not before thousands died.

Just as before, deranged individuals remain a greater daily threat than real terror attacks.