Nukes are always an option.
How many and where?
A friend of mine once told me that at work they had a "thought experiment;" you get a dozen nuclear weapons in the current US inventory. You get to pick the targets. I think it was a dozen, but for the sake of conversation we can make it a dozen. He even provided a neat tool called
Nukemap that used Google maps and had a listing of different warheads and stuff, that would put a circle of the appropriate diameter showing 100% killzones, 50% killzones and the persistent radiation zones. Had tools for airburst/groundburst etc, was pretty neat. I think you could save your "work" and create a link to it that you could share. It looks like that thing is broken, maybe it's my browser it's been a few years.
My "solution" was to drop 11 in a ring around Mecca on the land only, since it was my understanding that it is a requirement of Islam that one make a pilgrimage at least once in one's lifetime, on foot to Mecca if able. I was advised that nuking Mecca itself was probably a bad idea, so I used the map to create a radiation zone around Mecca that would be impassable on land. You could still make the hajj, but it would probably be one of the last things you did as walking through the radiologically active zone would probably not be too healthy... The 12th nuke I elected to keep in reserve.
Apparently his buddies back at the intel shop thought my "solution" was both elegant and amusing.
-p
ediot: got it to work in a different browser, here's my "solution," I don't think the Saudi Arabians would appreciate it:
https://nuclearsecrecy.com/nukemap/?t=f74e3bb7d2d3930f4f611b19b3492f07