I would argue you are applying an invalid precedent.
I'm thinking of Arabs who would suddenly be totally lost. There has never been such a loss to Christians. Jerusalem has always been there.
Well, perhaps my analogy could have been better, but I suppose my point is that a fanatic isn't really lost if he knows where you live. I.e., people can live for their hatred, like Captain Ahab, as well as for inspiration or the pursuit of happiness. I would argue that lots of Muslim jihadis are doing it already, and that they certainly wouldn't stop if we removed their golden milepost.
Excavating and ejecting the dust of Mecca into outer space would be more in the nature of revenge and (on the innocent bystanders) mass murder.
The moral problem with using WMD is precisely that they are extremely indiscriminate and recall Abraham's bargaining with God for the people of Sodom and Gomorrah.