[AcGold]

I'd stop dropping bombs and instead assemble a special strike team of several countries. Get the seals, some black ops guys, the military elite from every country in the NA/European coalition and go hunt them down one night or over a few days.

Find their bases of operations and take them out, spend a few hundred million to do so. More bombs and war will just cause more neglected youth to join these psychos in 20 years. Hunt them down and take care of the problem, declaring war will just create a cycle of escalating violence. If the US can find Saddam hiding in a hole they can surely band together to take out a group of extremists. 1000 elite military personnel with advanced weapons would be able to hunt down the core of this group. It's an ideology so twisted that if you take away the source the ideology can't stand on its own.