Doesn't sound nutty to me.
HOWEVER
The threat and even the follow through on a you-bomb-me / I-bomb-you policy will not discourage the muslim fundies-- they don't care if they die, nor do they care if a million innocent muslims die if it's for their cause.
I doubt also they'd give a rat's ass if a "holy" site was bombed for the same reason. In fact, they'd probably revel in it, wrap themselves in it and proclaim us all the more worthy of death for it.
Obviously, once we get to the point of nuking Mecca, the gloves are off. The terrorists can only continue as is because they are reasonably certain we won't respond in that fashion. They can't stand up to our arsenal if we actually use it.
"I doubt also they'd give a rat's ass if a "holy" site was bombed for the same reason. In fact, they'd probably revel in it, wrap themselves in it and proclaim us all the more worthy of death for it."
Exactly, they would build tombstones in the crater where all the 'holy martyrs' fell.