Gen. David Petraeus, then the American commander in Iraq, quieted the Sunni opposition to the American-backed Shi’ite majority government by giving them money and weapons. By doing so the U.S. rebuilt the Sunni military capability that it had ruined in 2003 when it destroyed the government of Saddam Hussein. With the fighting capacity of the Sunni minority now on par with the Shi’ite-majority government army, as we saw in the fall of Mosul to the Islamic State of Iraq and Syria.

I have nothing to add to what I wrote four years ago about the bungling of the Bush administration as compounded by Obama. The present disaster in Iraq is not wholly of our making, but American policy was a key enabler. The “surge” made it inevitable. There will be no resolution now without the exhaustion of the contending forces, in a long war of attrition with dreadful consequences for civilians, starting with the 500,000 who fled Mosul this week.