There suddenly was an American terrorist group by, let's say, the name of "The Minutemen". And, these Minutemen terrorists threatened any Islamic country by blowing up Mecca or the Temple Mount if any more acts of war were waged on Americans anywhere in the world? Would that get anyone's attention?
That's the road I think we should take, except that we need not create a terrorist group ourselves. We should just point a nuclear missile at Mecca, announce to the Arab world that Islamic terrorists of all stripes are now their problem and their problem alone to deal with if they wish for Mecca not to become a smoldering crater of glass. We will provide them with every aid and incentive that they might desire to save their most holy city and root out the terrorists once and for all, but if the terrorism begins anew, they have no one but themselves to blame for what happens to Mecca if they allow their madmen to get out of control one more time.
We've been reasonable through the bombings of embassies, the bombing of the USS Cole, the numerous suicide bombings of Palestinian nutcases in Israel, but it is clear that being "reasonable" hasn't gotten us anywhere. It's now time to become unreasonable.
This will scare any holy warrior.
The Osama's of the world would love such an ultimatum. They'd trumpet it as a declaration of war on Islam, and recruiting of unemployed youth in the failed societies they blame on the U.S. would explode, as would the less overt help of millions of the others imprisoned in the cruel bondage of Islam.