It is spilling:
Iraqi troops shot dead at least four people during clashes with Sunni Muslim protesters in Falluja on Friday in escalating unrest against Shi'ite Prime Minister Nuri al-Maliki. ...
Thousands of Sunnis have taken to the streets to protest against mistreatment of their minority sect since late December, increasing worries that Iraq could slide back into widespread sectarian confrontation.
Unfortunately, too many Sunni Arabs either actively or passively support al Qaeda terrorists who kill Shias. This isn't just a case of Maliki trying to screw over the Sunni Arabs. Fallujah has long been a problem and it still is, I see.
Our presence in force in Iraq, even if the conventional brigades were largely confined to large bases, could have helped the government wipe out the terrorists and would have reassured factions that nobody could get away with resorting to force to settle disputes.
Iraqis may yet work this out and it will be fine, but I'd feel the odds are better if we were there.