Reflecting on some scary Arab-Kurdish violence in Iraq’s Diyala province, Juan Cole wonders about a goal not attempted on Vice President Biden’s just-completed trip to the country:

He should have had a fourth goal, of Arab-Kurdish reconciliation before the US loses its leverage, but that issue appears not to have been central to this trip.

I admire Juan’s impulse. But to achieve Arab-Kurdish reconciliation before September 1? Or before the December 2011 departure of U.S. troops? Is that realistic? Remember that the Iraqi constitution originally said that the final status of Kirkuk — does it belong to Baghdad or Erbil or what? — was supposed to be resolved by 2007. But pretty much everyone, from the U.S. embassy to the U.N. to Baghdad to Erbil, conceded that the better part of valor would be to keep deferring a final decision on the city’s status until ethno-sectarian tensions subside.

Now, it may be that they won’t, and one of the reasons they won’t is because… Kirkuk’s final status remains unresolved. But if so, it’s difficult to see how United States intervention could actually unlock what probably is going to remain Iraq’s most vexing existential question.