We might be able to learn something from the strategy the British used in India to put an end to the Thugs. There were thousands of them, no one knew just who or where they were, or how they were organized, and for centuries they had secretly been murdering people--hundreds of thousands of them--in the name of their god. But a few were caught, and threatened with hanging if they did not inform on others. And the ones they informed on were then given the same choice. Some Muslim jihadists may not be afraid to die, but I am sure that's not true of all of them. The Japanese during WWII were even more fanatic than Muslim jihadists, and yet after a while, not enough volunteers could be found to fill the need for kamikaze missions.