Are there any sane people who think that bombing the holiest site of the Islamic faith would actually deter Muslim extremists from attacking the United States? Although you have to love the idea of deciding who you will attack in retaliation before you even know who has attacked you, or hell, that you'll be attacked. It's so very... PNAC.
Equally amusing is the fact that people who promote this ideas probably consider themselves realists. But anyone with a firm basis in this reality knows that getting the US defense establishment to consider military action against Saudi Arabia would be about as likely as convincing the same folks we should stop sending bombs to Israel.