Bombing targets
Bombing religious sites like Mecca would be a real lousy idea. This is the kind of culture that would still be taking it personally a thousand years from now. Hell, some Muslims are still pissed about the Crusades.
Thank God I don't have that kind of cultural memory. My own distant ancestors were harshly dealt with in Eastern Europe, but who cares anymore? Maybe the difference between civilizations and cultures that can advance vs. those who stay stuck in the Middle Ages is just simply being able to let go of the distant past.