Well, the good guys are about to put the boots to the bad guys in Mosul.
And that's a good thing, of course!
Read around a bit and you'll find plenty of stories that claim thousands of Mosul jihadis have already been spirited to Raqqa in Syria. By the US allies.
Yup, no point killing them in Iraq if they can be useful in making regime change in Syria,
I suspect the Mosul operation will go swimmingly well.
The Raqqa operation, not so much.