Mecca, Medina, Qom, the Dome of the Rock....Kboom.
Uh.... what country is Kboom in?
So, if we’re attacked by Iran, the idea is to not only nuke a nominal ally (Saudi Arabia), but also to destroy something located on top of the single holiest site in Judaism (the Temple Mount).
Can you see where that might be a tad bit problematic?