How to win a religious war in one step:
Destroy the other side’s most venerated religious symbol utterly.
In the case of Islam, allah is the supreme god, is all powerful, and has predetermined everything - down to the subatomic scale.
Allah is embodied in the stone at Mecca. Destroy that - allah is instantly discredited as the supreme god and shown not to be able to control anything.
When asked - shortly after 9/11 - what would they do if Mecca was destroyed, jihadis replied that allah would be discredited, and they would variously become Christian, Jews, or atheists. They added that there was no way they would humiliate themselves by praying to a discredited god. Asked if that action would make them mad and want vengeance, they said, no. For what? Allah was a false god and not to be respected or revenged for allah’s deceit. (This interview was posted somewhere on the web at the time.)
The best way, as the jihadis would see it, would be to make a huge statement without warning, like 9/11. The best way to accomplish this, from the Western point of view, would be without warning to take out Mecca during the ‘haj’ with a modestly small thermonuclear weapon.
The radioactive spot would continue to remind former jihadis of their humiliation and of the false god, allah.
The near total loss of Saudi oil would be made up, in time, by other nations, principally Russia and the US.
While many here and elsewhere would decry this as bloodthirsty and vile, the upshot would be to end over 20 wars the jihadis are currently engaged in fighting against their neighbors merely because they are not muslims.
There is no way, as others here have noted, to talk them out of continuing to wage war until everyone on Earth is muslim (Sunni), or conversely until everyone on Earth is brought to Paradise (Radical Shiia).
The choice for the Western world is to continue in a hodgepodge fashion, fighting one group here and another group there for generations, or take the bull by the horns and end it quickly as cleanly as possible.
I agree with you about wiping Mecca [and the other holy sites for that matter]. Could the mudslimes hate us any worse than they already do? Would their pagan god be discredited? Would they bow to a smoking crater? There’s only one way to find out. Perhaps we could appease the squeamish by using conventional bombs instead of nukes. As other posters have said, killing 2 billion pagans isn’t feasible. Destroying their holiest shrine is.