As the conflict between the U.S. and Iran simmers, there is a mounting fear within Iraq that a conflict of another kind could take shape amid the upheaval: A terrorist comeback from the remnants from the Islamic State, or ISIS.

Nearly a week after a U.S. drone strike killed Iran’s top military commander Gen. Qasem Soleimani near Baghdad International Airport, regular Iraqis and officials see his death as a blow to their fight against the terrorist group, which was almost entirely crushed in 2018 after a four-year war, fought by the U.S.-led coalition and a collection of Iraqi military forces and militia groups, as well as some Iranians themselves.

“People are talking not only about ISIS but a new version that might arise now,” Dhia Al-Asadi, an Iraqi politician and former Member of Parliament aligned with Shiite cleric Moqtada Al-Sadr, told TIME by phone on Wednesday. “Soleimani is going to be missed by almost all those who were serious about fighting against Al-Qaeda and ISIS.”

The U.S. strike against Soleimani has handed the ISIS remnants an unwitting victory, by stoking anger among Iraqis against the group’s archenemy, the Americans, and diverting their attention from other grievances.

For several months this fall and winter, tens of thousands of Iraqis poured into the streets in giant protests against government corruption and against Iran’s dominance in their country, nearly bringing Iraq to a standstill and forcing Iraq’s Prime Minister Abd Al-Mahdi to offer his resignation; he remains as a caretaker head of government while the fractious parliamentary groups squabble over who will succeed him.

But in recent days, that discontent has been swept aside, as Iraqis brace for what might come next. As head of Iran’s Islamic Revolutionary Guard Corps, or IRGC, Soleimani crafted the ground tactics against ISIS, training Shia militia groups to fight local battles, including helping drive ISIS out of Iraq’s second city Mosul in 2017 in the biggest urban warfare since World War II.

“The war against ISIS was America in the air and God on the ground,” says Mowaffak al-Rubaie, a former Iraqi National Security Advisor, by phone from Baghdad, referring wryly to the Shia militia as “God;” many Shia joined the fight against ISIS after appeals from clerics.

The battle against ISIS created a curious wartime alliance between the U.S., with its heavy firepower, and Iran, with its deep penetration into Iraqi communities. Yet it is unclear how closely they cooperated. Hundreds of secret Iranian intelligence documents, leaked to the news site The Intercept last November, exposed vast Iranian influence in Iraq, much of it stitched together by the hugely powerful Soleimani. But it also included one document dating to the four-year battle against ISIS, in which Iranian intelligence officers complained about “The Americans’ insistence on not cooperating with Iran in the war against ISIS.”

In the aftermath of ISIS’s defeat, many Iraqis credited Iran for the victory. “Without Soleimani, the ground war against ISIS would have been much weaker,” Al-Rubaie says. Now, he says, “There is a very good chance that ISIS will come back.”

On Sunday, the American-led coalition that has been fighting ISIS in Iraq and Syria since 2014 said it had “paused” its campaign against the group in Iraq in order to protect the Iraqi bases that host coalition troops, giving another strategic opening to the group.

Just a few thousand ISIS fighters are believed to have survived the war, driven underground and scattered in different parts of Iraq. Its leader Abu Bakr Al-Baghdadi blew himself up last October in Syria’s Idlib province, during a U.S. operation to capture or kill him, according to President Trump’s account.

Those ISIS fighters left alive are severely weakened. “They are not a threat yet, but they are not gone,” says Renad Mansour, senior research fellow and director of the Iraq Initiative program at Chatham House, or the Royal Institute of International Affairs in London.

While the combined military forces crushed ISIS, Mansour says Iraq’s enduring problems of corruption and dysfunction—which he believes partly allowed ISIS to flourish in the first place—remain. “It was a military solution, but not a political solution, about why this group was able to emerge and take over so much of Iraq,” he says. The group could take advantage of the Iraqi government’s dysfunction after months of protests to once again rally people to their cause, as they have in the past. “They wait and see that the Iraq government is not being effective.”

If ISIS or an outgrowth of it does emerge from the crisis, the U.S.-led coalition would likely unite rapidly to fight it. In addition, Mansour says Soleimani’s death has helped to unify Iraq’s rival Popular Mobilization Forces, which waged the ground battle against ISIS, and have battled each other for political control since their battlefront days. Those divisions, like the street protests, have also been engulfed by the crisis in recent days, perhaps making the militias a force in any future anti-terrorism fight. “One of the biggest immediate impacts is the unifying of the Shia political bloc,” he says.

But this week at least, the U.S. appears isolated in its war talk against Iran. Some of its closest allies have been scrambling to staunch the conflict and to deal with the fallout of Soleimani’s death, in part fearing that a spiraling conflict could send fresh waves of refugees fleeing in their direction.

In a long phone call on Tuesday, French President Emmanuel Macron appealed to Iranian President Hassan Rouhani to “abstain from taking any action that would aggravate mounting tensions,” according to the Elysée Palace, and to stick to the 2015 deal, negotiated by the U.S., the European Union, and the United Nations, in which Iran agreed to halt its nuclear enrichment program. Iran said on Sunday that after the U.S. strike against Soleimani, it no longer felt obligated to abide by the deal, a move that could trigger new sanctions against Iran; President Donald Trump has already withdrawn the U.S. from the deal, which Europe has struggled to keep alive.

The French leader also told Rouhani on Tuesday that France, which has troops in Iraq, was committed to “Iraq’s sovereignty and security,” and that the “sole objective” of the U.S.-led military coalition in Iraq was to fight ISIS, according to the Elysée.

Soleimani’s death has already complicated the coalition’s presence in Iraq. The Iraqi parliament took a non-binding resolution on Sunday to expel U.S. forces from the country, and, after the coalition announced the suspension of its anti-ISIS activities, Germany, Canada and Croatia have all said they intend pulling some forces out of Iraq, for fear of being embroiled in a U.S.-Iran war.

Such a war would be calamitous, says al-Rubaie, adding that the talk on the streets of Baghdad since Soleimani’s death has been“all war.”

“It will not be short, with a winner and a loser,” he says. “It will be a long, protracted, suffering war in the region, and the beginning of the end of the American presence in the region.”

That could be bad news for the fight against ISIS, whose resurgence is a deep fear among Iraqis. “It has already been a concern, even before this event,” Mansour says, referring to the U.S. strike last week. “Now American troops are being forced or asked to leave, and the troops are there to fight ISIS.”

Good news, then, for those ISIS fighters still left alive.

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