You're probably right about us "not going to do that".
The "point of this bluster" is to suggest that such a policy of retaliating against Mecca is probably a good deterrant, given the value the Muslims place on it.
It's obvious that the terrorists aren't rational, and can't be reasoned with. There is a word for that: barbarians. Barbarians, do however, understand fear, and the US should exploit the weirdness of their desert-demon religion to scare the hell out of them.
I believe you're underestimating the enemy. Suicide bombers are barbarians. The people who orchestrate the terrorist activities of the barbarian masses of the Middle East, however, are not barbarians. They are people of intelligence and cunning. And they have at their disposal, tens of thousands of unthinking and unquestioning barbarians. I wouldn't underestimate someone like that.