A city west of Mosul is poised to become the 'city of revenge' for Iraq's powerful Shia militias

Tal Afar, a city 40 miles west of ISIS-held Mosul, is poised to become "the city of revenge" for Iraq's powerful Shia militias who were forced out of the city after an insurgency by the Islamic State's predecessor, al-Qaeda in Iraq, in 2005.

"The scene is set for an extremely dangerous episode to unfold in Tal Afar, between Shia militias, who are seeking revenge for the devastation wrought on them by Sunni jihadists since 2005, and ISIS fighters who, if history is our guide, would prove to be highly capable in their defense of the town," Gareth Stansfield, a Global Fellow at the Wilson Center and professor of Middle East politics at the University of Exeter, wrote earlier this month.

Shia militiamen backed by Iran - known as the Hashd al-Shaabi - have already begun the move to recapture the strategic city.

On Wednesday, the head of the Iran-backed Shia Badr Organization Hadi al-Amiri announced that the militias had successfully re-captured Tal Afar's airport from the Islamic State in what "will be the starting block for the liberation of all the area...to the Syrian border and beyond the Syria border."

Sunni-Shia relations have long been brutal in the city, as described by war reporter George Packer in a 2006 article for The New Yorker:

"The mayor was a pro-insurgent Sunni. The police chief, appointed by the government of Prime Minister Ibrahim al-Jaafari, was a Shiite. His all-Shiite force was holed up in an area of high ground in the middle of the city known as the Castle, which is surrounded by sixteenth-century Ottoman ramparts. Unable to control the city, the Shiite police sent out commandos to kidnap and kill Sunnis. Outside the Castle, radical young Sunnis left headless corpses of Shiites in the streets as a warning to anyone who contemplated coöperating with the Americans or the Iraqi government. Shiites living in mixed neighborhoods fled."

"The Shia and Sunni communities fell in on themselves," Colonel H. R. McMaster, the commander of the 3rd Armored Cavalry Regiment who were stationed in Tal Afar at the time, told Packer. "They became armed camps in direct military competition with one another."

Recapturing Tal Afar from ISIS would mean severing one of the jihadists' last remaining corridors from Iraq into Syria.

"The worst [ISIS] killers of all come to Tal Afar," a senior Iraqi official told The Independent on the condition of anonymity earlier this week.

But the city's liberation will inevitably be tinged by sectarian motivations.

"We are coming to Tal Afar to avenge Hussein," Qais al-Khazali, the leader of the Asaib Ahl al-Haq Shi'a militia, said in Baghdad last month, referring to the third Imam of Shia Islam.

The Turkish wild card

Another wild card that could further complicate the impending battle for Tal Afar is Turkey, which feels an obligation not only to protect Sunni Turkmen in the city but also to quell Iran's influence in northern Iraq and Syria by keeping the Iran-backed Shia militias at bay.

Turkey infuriated Baghdad - and its Russian and Iranian allies - last December when it ignored Iraq's request to stay out of the Mosul battle and deployed roughly 500 troops to a military base near Bashiqa, Iraq, to train and advise local forces.

Tensions have been growing between the Turks and the Iraqis ever since.

In late October, Turkey's president, Recep Erdogan, reiterated that "Tal Afar is a very sensitive issue for us. We definitely do not regard [the militia's involvement] positively in Tal Afar and Sinjar. I already told this to officials clearly."

He warned that Turkey's response will be "different" if the Hashd al-Shaabi "terrorizes the region."

It's unlikely the Hashd will back down from Tal Afar, however.

"Tal Afar is the real target for the Hashd al-Sha'abi, because unlike Sunni-dominated Mosul there was a significant Shia population in Tal Afar when the city fell to ISIS in 2014," Michael Knights, a fellow at The Washington Institute specializing in the military and security affairs of Iraq, Iran, and the Persian Gulf, told Business Insider.

"Tal Afar was the northernmost stronghold of the Shia militias and they want it back," he said.

Knights added that the chances of a violent conflict erupting between Turkish soldiers and Shia militiamen in the city are still low, however.

"So many actors are focused on preventing a Turkish-Hashd conflict," Knights said. "Turkey knows that going to war with the Hashd means going to war with a major neighbour, Iraq. Many international actors would work tirelessly to avoid such an outcome before it unfolded - and indeed they are warning and shaping the actions of both Turkey and the Hashd now behind the scenes."

Ayham Kamel, an expert on Iraq and the Levant at the political risk firm Eurasia Group, said he thinks that, like Mosul, Tal Afar is equally important to Turkey and the Shia militias - and even more sensitive from a sectarian perspective.

Still, he said, "I don't think there's a high risk of a clash. Iraqi forces will lead the way, not the Shia militias. In my view, the city will remain divided and very difficult to govern."

The commander of Mosul's police force, Staff Gen. Wathiq al Hamdani, told the New York Times that the Hashd "will take the desert," but that Iraqi security forces will take the city itself.

"It's a very difficult axis," he said, adding that Iraqi troops "have no problem" with the Hashd playing a role in driving ISIS out from the city's outskirts.

"As long as they stay away from the civilians," he added.