The US is out of good options for fighting Islamic State extremists.
The Iraqi army, which the US has tried to build up into a viable fighting force, fled when faced with dozens of car bombs in the provincial capital of Ramadi.
Arming Sunni tribes to fight the Sunni extremists in the Islamic State terror group (also known as ISIS, ISIL, and Daesh) would likely be America's best option. But, as Aaron David Miller noted in The Wall Street Journal, this could undermine Iraq's central, Shia-dominated government and make Prime Minister Haider al-Abadi look weak to his Shia constituency.
Consequently, Baghdad has not agreed to arm Sunni tribes.
On the other hand, Shia militias backed by Iran have so far proven to be the most effective fighting force against ISIS, but many fear that they are pursuing a sectarian agenda and committing atrocities against Sunni civilians in the areas they liberate from ISIS.
Shia militias are now leading the charge to retake towns near Ramadi, the Sunni-dominated capital of Iraq's Anbar province, from ISIS militants. And Iranian commanders are fighting on the front lines.
The flag of Iran-backed Kataib Hezbollah, a militia that the US considers a terrorist organization, has been spotted in the retaken areas, according to The Washington Post.
The Iran-backed Badr Organization, which fought and killed US troops in Iraq after the 2003 invasion, also has a part in the counteroffensive to regain control of Ramadi.
Abadi asked Iraq's popular-mobilization units, which include the Iran-backed Shia militias, for help in Anbar after Iraqi Security Forces there crumbled. Officials now claim that the militias are working alongside the Iraqi army.
And the US appears to be backing the campaign led by proxies of Tehran.
Air Force Col. Patrick Ryder, the CENTCOM spokesperson, recently told reporters the US will provide air support "to all forces that are under the command and control of the government of Iraq," which now include the Shia militias.
This is despite CENTCOM head Gen. Lloyd Austin telling US lawmakers in March that he would not "coordinate or cooperate" with Shia militias.
The US appears to be justifying this through Iraq's claim that the Shia militias are working in tandem with ISF, but, as the Post report makes clear, the militias claim they're really the ones running the show in Anbar.
“We wish the army could be at the same level as the [popular-mobilization units],” a Kataib Hezbollah fighter told the Post near Ramadi. “In reality, they are much weaker.”
The apparent shift in US policy toward Shia militias signals the acceptance of a dark reality in Iraq — that without the Shia militias, ISIS might be able to further consolidate their gains in Iraq.
Relying on Shia militias is far from a perfect solution, however, even if US officials are willing to overlook the fact that some of these militias have American blood on their hands.
As noted in The Journal, the US allowing Shia militias to take a greater role in fighting ISIS "guarantee[s] a perpetuation of sectarian tension between Sunnis and Shiites — an outcome that benefits ISIS, whose extremists see the sectarian divide as a way to capitalize on Sunni disaffection and boost their own influence."
In other words, as Shia militias charge into Sunni areas of Iraq, ISIS can market itself as the only force that can protect Sunni civilians in these areas.
And the Shia-dominated government in Baghdad has been reluctant to take in Sunnis fleeing ISIS, bolstering the perception that the Sunnis can't count on the government for help.
So while Shia militias might be effective at beating back ISIS, their involvement comes at a price — worsening sectarian tensions in a country that doesn't stand much of a chance at stability as long as vicious fighting persists between the two sects.
