In an opinion piece in the New York Times, Mr. Grenier offers very simple and succinct advice about what not to do in engaging ISIS, from the article:

At the outset of the war in 2001, I argued that it was critical for Afghans to lead the anti-Taliban campaign. My advice was followed at the time because we were initially successful. Even if Mr. Karzai and Mr. Shirzai had failed, though, my advice would have been the same — though I doubt anyone in Washington would have listened to me. I would have counseled strategic patience: Do not try to do in place of Afghans what only Afghans can sustain over the long term. In the fevered post-9/11 political environment, patience would have been a nonstarter.

The impulse to do something about the ISIS barbarians who are slicing off heads for YouTube stardom grows with the posting of each new video.  But we should ask ourselves, why are they so openly publicizing their barbarity?  And the obvious answer is that ISIS is trying to provoke the West into doing something.  At least Mr. Grenier gets it, again from the article:

Sadly, America has learned very little from the experience in Afghanistan. Just listen now to the impatient voices emanating from the right concerning the Islamic State. Our allies in Iraq, they say, are hopelessly ineffective, and our allies in Syria practically nonexistent. ISIS poses a clear threat to American security, they insist: If others will not, or cannot defeat it, we should not be afraid to step forward ourselves to crush it.

These sentiments play to the instincts of many Americans, and they must be resisted at all cost. If the United States were to take the lead in the ground war in Iraq and perhaps eventually in Syria by introducing conventional combat forces, we would feed into a radical Islamist narrative that pits the invading armies of the crusader against the committed defenders of Islam. In the process we would only strengthen the appeal and the morale of our enemies, while weakening and demoralizing our friends.

This is, very simply, the most clear-headed thinking I have yet seen as regards ISIS.  We are fools to let them draw us into a full-scale war.  Doing so would only enhance their appeal, perhaps even to more of our own citizens.

Alas, full-scale combat operations are practically inevitable.  Almost two-thirds (62%) of Americans recently polled by Quinnipiac University want ground troops fighting ISIS, according to an article on Bloomberg.

I can only imagine that the reason so many want to rise to ISIS’s bait is because the notion that someone else does the fighting has by now become completely internalized in the American psyche.

Personally, I have a moral aversion to wars of choice, and this would be a war of choice.  But more importantly, the war would be ineffective, except at enhancing the prestige and allure of ISIS to our detriment.  Sure, we could beat them in battle, but doing so would only reinforce the ISIS narrative of the West as crusaders come to oppress the Arabic Muslim world and cause anti-Western sentiment to ramify into areas that today consider us friends.

Why do we always ignore the experts on the ground, except as a last resort?