The U.S. is struggling to stop a new civil war in Iraq

Since 2014, the U.S. has rallied an unlikely coalition of allies, and adversaries, in the Middle East to fight against one common enemy: ISIS.

Now, with the terrorist group’s caliphate on the verge of collapse, the U.S. is confronting its next great challenge: How to keep members of the winning side from tearing each other apart?

Washington now faces tough choices between feuding allies, analysts said, while it tries to contain the rising influence of another power player in the region: Iran.

Early indications suggest things are not going Washington’s way.

“The U.S. is in a very difficult position,” Nathaniel Rabkin, managing editor of the newsletter Inside Iraqi Politics, told VICE News. “The anti-ISIS coalition is a victim of its own success. It’s losing the common enemy.”

This was immediately made evident last week, when fighting erupted between Iraq’s federal government and the autonomous province of Kurdistan, leaving the U.S. with little recourse but to implore both sides to use dialogue to resolve their differences peacefully.

The Iraqi army, joined by Iran-backed Shia militias, surged north in a surprise attack to capture the oil-rich region of Kirkuk in a stunning defeat for Kurdish peshmerga forces, which had held effective control of the region ever since Iraqi forces abandoned Kirkuk while retreating from ISIS in 2014.

In the face of military defeat, the Kurdistan Regional Government on Wednesday offered to “freeze” the results of their Sept. 25 referendum on independence from Iraq, which had enraged Baghdad, and enter dialogue. But as of this writing, the Iraqi government, which demanded the referendum be “annulled,” has yet to respond.

With their defenses overrun, Kurdish leaders are now fuming over America’s reluctance to do more to deter Baghdad’s assault — despite the Kurds’ willingness to shed blood in the name of the U.S.-led fight against terrorism.

“People are being killed here,” Safeen Dizayee, chief of staff to the prime minister of the Kurdistan Regional Government, told VICE News. “We expect the international community, particularly the U.S., to put pressure on Baghdad to cease its hostilities.”

The unrest has already resulted in civilian deaths, according to Amnesty International. The human rights group said in a report Tuesday that in the city of Tuz Khurmatu alone, hundreds of properties were looted and set on fire in “what appears to be a targeted attack on predominantly Kurdish areas of the city.” The report cited eyewitnesses blaming Iraqi government forces and the militias. At least 11 civilians were killed in “indiscriminate attacks,” and 35,000 people have fled the city since Oct. 16, the report said.

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To Dizayee, the events came with an unsettling sense of déjà vu. He recalled America’s unwillingness to stop Saddam Hussein’s brutal assault on the Kurdish people in 1991 following the first Gulf War. Back then, the Kurds had responded to President George H.W. Bush’s call for the Iraqi people to rise up against the dictator. Thousands of Kurds were then slaughtered by Saddam’s helicopter gunships.

“It’s bringing back the negative images of 1991, when people fled from Saddam’s wrath,” Dizayee said, before adding, with tension in his voice: “We are disappointed in the lukewarm position of the United States in general.”

President Donald Trump had declared the U.S. would remain neutral, even though Baghdad’s forces cruised to victory last week atop U.S.-supplied M1 Abrams tanks.

Some observers said American neutrality was really just another way of taking sides. The position was, in effect, a strategic decision to back Baghdad as the most effective bulwark against the growing influence of Iran — even if that came with the regrettable consequence of abandoning a smaller ally, Kurdistan, according to Michael Knights, an expert on Iraq at the Washington Institute for Near East Policy.

“The U.S. just made a grown-up choice to play hardball geopolitics,” Knights told VICE News. “We’re always saying the Iranians play chess and the West plays checkers. Well, the West just played chess. And in chess, you sacrifice pieces, even though that doesn’t feel good to Americans.”

Ironically, Iranian and Arab social media interpreted these latest military developments as a victory for Iran and a defeat for the United States, Knights noted — presenting a grave risk to U.S. credibility if it could not be seen, publicly and demonstrably, to be telling Baghdad when “enough is enough.”

This was not lost on U.S. National Security Advisor H.R. McMaster, who last week worried openly that Iran was exploiting Iraq’s instability to pursue “hegemonic aims” across the Middle East.

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With the country tipping toward greater conflict, America’s top diplomat, Rex Tillerson, made an unannounced trip to Baghdad Monday to try to contain the fallout. But he quickly ran up against the limits of Washington’s influence over the fractious country.

Tillerson issued a blunt statement saying the Iran-backed militias involved in the fight against the Kurds should “go home.” But Tillerson’s host, Iraq Prime Minister Haider Al-Abadi, tersely replied that the militias would stay, insisting the militias were part of Iraq and symbolized “the hope of the country and the region.”

Al-Abadi, held his defiant posture Wednesday, telling the Wall Street Journal he doesn’t want his country to become a battleground between the U.S. and Iran.

“What we are telling everyone, including our Iranian neighbors and the U.S., who have become our friends by supporting us in our fight against Daesh, is that we welcome your support, we would like to work with you, both of you, but please don’t bring your trouble inside Iraq,” Al-Abadi said.

Dizayee, the Kurdish official, said that if the U.S. goal in Iraq is now countering Iran, then tolerating the presence of the Iranian-backed Shia militias in anyway makes little sense.

“Iran has not hidden its agenda: They are openly seeking influence in Iraq and trying to impose their hegemony over this region,” said Dizayee. “With all due respect, if our friends in Washington are not aware of that, it’s too late in the day to make them aware.”