The civil war in Iraq over the last three years touched off by ISIS may just have been an appetizer. Late yesterday, the Iraqi army attacked Peshmerga forces around Kirkuk in an attempt to wrest control of the city and its oil production away from the independence-minded Kurds. The Shi’ite-dominated government in Baghdad has thus far only used the army for this operation, but Shi’ite militias with ties to Iran wait on the sidelines — and that may be one reason why the Kurds are balking at federal control:

Iraqi Kurdish officials said early Monday that federal forces and state-backed militias have launched a “major, multi-pronged” attack aimed at retaking the disputed northern city of Kirkuk.

Kurdish forces known as the peshmerga were digging in at the edge of the international airport after withdrawing from their positions outside the city. Hundreds of armed Kurdish residents were taking up positions inside Kirkuk anticipating an attack. …

Iraq’s Interior Ministry said in a brief statement that federal forces have taken control of a power plant, a police station and industrial areas near Kirkuk. It provided no further details on the fighting or casualties in what it referred to as Operation Impose Security on Kirkuk.

Thus far, the Popular Mobilization Forces are staying out of the fight, but that may not last long if the Peshmerga gain the upper hand:

Iraq’s state-sanctioned militias, the mostly Shiite Arab Popular Mobilization Forces, were ordered to stay out of the city, according to al-Abadi’s office, and instead keep positions in the countryside. They are viewed with deep suspicion by Kurdish residents, who see them as beholden to Iran rather than Iraq’s central government. The predominantly Shiite militias are sponsored and guided by Tehran.

The Washington Post reports that the militias have already declared their intent to enter the city.  In fact, they may have precipitated the firefight with an ultimatum:

As Kurdish authorities warned they were about attack, Abadi tried to defuse tension, taking to Twitter to assure that Iraqi forces “cannot and will not attack our citizens.” Iraqi commanders initially dismissed troop movements as routine deployments aimed at securing nearby Hawija, recently recaptured from Islamic State militants.

But Shiite militia leaders close to Iran said that they were there to move into the province and had presented a list of demands to Kurdish Peshmerga commanders.

Those demands included a Kurdish withdrawal from positions including the city’s K1-military base and oil fields.

“The orders are to surround K1 and oil fields and stop and call on the Kurdish forces to retreat,” said a counterterrorism officer who declined to be named because of the sensitivity of the topic. “There are strict orders to avoid violence.” But militia commanders took a more combative tone. Anyone who fights Iraqi forces is “the same as ISIS,” said Karim al-Nuri, a spokesman for Iraq’s mobilization units. State television said that counterterrorism forces, the 9th Division of the Iraqi army and federal police forces had taken “large areas” of the province without a fight. It said popular mobilization units took positions “outside Kirkuk.”

So much for “routine deployments.” The Iranian-backed Shi’ite militias appear to be driving this outcome, forcing Haider al-Abadi to act with force against the Kurds — and thereby confirming the Kurds’ worst fears about the Iraq federation’s future direction. If Iraq falls completely under Iran’s thumb, it will spell the end of the autonomy that Kurds have enjoyed since the end of the 1991 Gulf War.

The Kurds feel they have a separate claim on Kirkuk, too. The Peshmerga essentially saved Kirkuk from ISIS three years ago after the collapse of the Iraqi army, which ignominiously fled the region and left it open and unprotected. Ever since then, the autonomous Kurdish government has insisted that the city and its environs belong under their control, while Baghdad has insisted on a return to the status quo ante. Complicating matters is the lucrative oil industry in the Kirkuk region, which both sides want to control. It would have meant tense negotiations under any circumstances, but the referendum last month for full independence provided a catalyst for another civil war.

This puts the US in a very tough position. We still arm the Iraqi army as well as the Peshmerga, and we’re siding with the Syrian Kurd militia YPG over the strenuous objections of our nominal ally Turkey in the fight against ISIS. The Trump administration tried to warn off the Kurds from holding their referendum in the first place to no avail. How does the US see this firefight? Er …

BREAKING: US military says exchange of fire between Iraqi, Kurdish forces in Kirkuk a "misunderstanding."

— The Associated Press (@AP) October 16, 2017

That’s a political reductio ad absurdum. All war is at some level a “misunderstanding”; this falls more into the “inevitable” category. Abadi has basically stumbled back into the same situation that Nouri al-Maliki created by deputizing Iranian-backed Shi’ite militias for the fight against ISIS, which alienated the Kurdish and Sunni minorities all over again. By allowing them to take positions against the Kurds and to issue ultimatums to Irbil, Abadi may have made that alienation impossible to repair.