What makes you think another adventure in nation-building in the ME will turn out any differently than the two failed efforts we poured so much treasure and so many lives into?
We will not go in there like we did in WW II with saturation bombing of cities,e tc. For one thing, that is now a war crime. It's apparently ok for ISIS to cut the heads off prisoners, but we will be held to excrutiating standards by the international human rights handwringers.
How many lawyers do you think ISIS has in its ranks and how often are they consulted ? We had hundreds of them in Iraq, passing judgment on everything from which bullets were legal to who we could detain. Speaking of which, we had the leader of ISIS incarcerated in Iraq and let him go. Perhaps he didn't get his rights read to him correctly.
ISIS didn't just spring up like mushrooms after a rain. They get massive financial support. Where do you thnk it comes from? Our "allies" in Saudi Arabia, Kuwait, the Emirates and especially Qatar.
We should have let Saddam keep Kuwait, but he didn't have the DC lobbyists the Emir of Kuwait did.
My point is, we are not going to do the job right, so we should stay out. A start would be to pressure the sunni countries to cut off financial support, but we either aren't doing it or they are ignoring us. It's not like the other side, the shias, are any bargains either. Actually, they are the more radical islamists. The sunnis will fight to the death to avoid being ruled by shias, and who can blame them?