These crazed jihadis just keep coming though, that's the problem. Wherever there is a weakened government, they take root. (Afghanistan, Iraq, Syria). Iraq was a basket case in many respects under Saddam Hussein, but it was a stable basket case, and Al-Qaeda nor ISIS would have ever dared to set foot inside Iraq if he was still in charge. It seems to me the best way to destroy these terrorist groups is to try to stabilize (sorry Tony) these countries so there are no power vacuums to be exploited. We can bomb targets forever and they'll still keep coming, because the bombing only perpetuates the instability. ISIS wants and needs us to fight them, that's their whole raison d'être. So we can keep playing into their hands, and they can keep recruiting for the Holy War they're fighting.
An alternative strategy would be humanitarian missions, military engagement only in defense (sorry Tony) of refugees, and hardcore diplomatic efforts to try and get these countries more functional and less of a magnet and breeding ground for psychopaths.