I don't think we can deal with Daesh in the same way we can a nation-state. They don't exist on the same principles as Germany, France, the US, or the UK and are a part of a much broader spectrum. So we eliminate Daesh: march into Al-Raqqah and break down their command and take out or capture Bahgdadi. But what do we solve? Not really anything. The pretense of their activity as militant ultra-orthodox, almost apocalyptic Muslim philosophy still exists. We still got Boko Haram to deal with, Al-Qaeda to contend with, or Al Mourabitoun which encompass a extreme belief that transcends a single group or a perceived nation-identity. For Daesh at the least, their validity is derived from the idea that the west is out to get them. They believe in and want to instigate a war of the civilizations akin to the Crusades. And they want Muslims in the west to become disenfranchised with their native countries so they become militarized and turn to them; because Daesh becomes their salvation. In Syria and Iraq as well for the US or western powers to approach them with ground troops and to have a visible presence among the Syrian and Iraqi people again would validate for Daesh the west as being invaders despite their own instigation. This would help them recruit from the local region fighters that would attack us as soon as we get there because they want to kill us. And they want as many of us to approach them as possible. Really, attacking them will prolong the existence of this ideology by validating it. It's seeking attention from us and we should not give it to them. Accept the migrants so that Daesh has no one to rule and so that they become indebted to us through our charity. Or even: help people out of the occupied territories. Daesh's authority in the area is only really valid if there's anyone left. Most people that live in the affected areas of Daesh's control tend to flee so cities like Sinjar are often left totally abandoned and anyone who has had the means has left. If they are to be fought, then it's ideally best - for us at least - to not justify the East vs West clash of civilizations philosophy and get the east to fight the east. Daesh is as much a reaction to the west as Progressive Islam is a reaction to itself. Let Saudi Arabia fix the mutant afterbirth it enabled.