At least there is some ideology involved here. They do a lot worse than that in Mexico everyday...just for fun.
I agree with the ideology being an extremely important distinction between what goes on in Mexico and these isis f ucks. No one in Mexico has declared any intention of killing folks that don't share their beliefs. The Mexico brutality, I'd say, is motivated by greed/money.
Changing gears, how many feral hogs would fit on a big cargo plane? I can't decide if it is more fun to think of letting ten thousand live hogs loose over there or dropping them from 25000 feet with every 5th one frozen solid.