Late last year, Iraqi army intelligence issued a security warning for southern Salahadin, which it had recently recaptured: an Islamic State (ISIS) insurgent group threatened to kill Shiite pilgrims who were on their way to holy sites in Samara. Although the Iraqi military had made remarkable progress reinstating control over Anbar, Northern Diyala, and Salahadin, the news was sobering. More than anything, it recalled the kind of insurgent activity that plagued Iraq from 2004 to 2008, and it raised a question: can Baghdad really end the war?

Whatever the security forces might hope, after a defeat, ISIS members don’t simply give up their cause or switch their allegiance; they merely change their tactics. Just as ISIS members once came together from disparate groups such as Ansar al-Islam, Ansar al-Sunna, Tanzim Qaidat al-Jihad fi Bilad al-Rafidayn, and the Islamic State of Iraq, they now return to the safety of small insurgency units. Although these groups’ flags rotate regularly, the people carrying them remain the same.

One example is the ISIS insurgency cell operating in the marshlands near Lake Hamrin. ISIS once controlled the territory next to the marshlands, but it was liberated in December 2014. Now, one side of the area is controlled by Kurdish forces and Shiite militias, and the other is governed by the Iraqi federal government. This division of labor makes the marshlands a perfect territory for former ISIS members to conduct insurgency campaigns on both sides. Recently, they were even able to destroy the electrical towers that supply several villages.

A member of the Iraqi Special Operations Forces in a military vehicle during a battle with Islamic State militants in Mosul, November 2016.
Alaa Al-Marjani / REUTERS

This 100-strong insurgency group is presumed to be headed by a local, a 39-year-old ex-policeman named Ahmad Hassan Abd. He first joined al Qaeda in his home area and then left to fight elsewhere. Later, he and a small number of local militants appeared in the video of ISIS taking Mosul. Now that ISIS is losing territory, he’s returned to run an insurgency that is similar to al Qaeda’s in its tactics but operates under the ISIS flag.

Another insurgent, Abu Anass, a 38-year-old grocery truck driver from Northern Diyala, has a similar biography. Although not particularly religious, he joined al Qaeda in 2008. When ISIS came through, he immediately signed up and relocated his family to Mosul. At some point, he came back and is now involved with the Hamrin ISIS cell.

Men like these are very effective. Not only are they experienced in unconventional warfare, they are also familiar with the territory and are dedicated. But that is more out of necessity than choice. Their names and faces are inextricably linked with al Qaeda and ISIS, which means that they have few options other than continuing to fight. Their high visibility during the war makes it impossible for them to either defect or hide, and if Iraqi authorities catch them, they will serve lengthy prison sentences or face death. At this point, even a suicide mission would be preferable to surrender. ISIS itself has reported a recent uptick in the number of such operations.

Many locals aren’t talking—at least to anyone allied with Baghdad.

In addition to militants, ISIS insurgency cells depend on nearby civilian populations, some of which side heavily with the fighters. That, the small size and mobility of the insurgent groups, and the expansiveness of the territory make it difficult for security forces to pinpoint insurgents’ whereabouts. In turn, the forces have had to rely on civilian intelligence. But many locals aren’t talking—at least to anyone allied with Baghdad. Although weapons and ammunition still come from ISIS-held areas in Mosul and Hawija, local civilians provide much of the food, information, and anonymity.

Civilian support isn’t only based on fear. According to a survey conducted near the Hamrin area in October 2016, after it had been liberated by Kurdish forces, a significant number of people openly admitted that some aspects of life were, in fact, better under ISIS than they had been before it. In particular, people give high marks to the security provided by ISIS and the group’s court system. These people, even those who don’t actively support the insurgency, wouldn’t actively oppose another takeover either, whether by ISIS or a similar organization.

Iraqi soldiers pose with an ISIS flag in the recaptured town of al-Shura, south of Mosul, October 2016.
Zohra Bensemra / REUTERS

In such circumstances, the insurgency near Hamrin and others like it could go one of two ways. On one side, it could become less active with time. As Mosul and Hawija fall, insurgents will lose not only their main source of weapons and ammunition but also morale. Hurting matters is that the civilians on which the group relies are in very bad situations themselves. Multiple displacements have left them with barely enough food to support themselves, never mind a band of fighters. Sherzad BawaNuri, who led the Kurdish insurgent movement against Iraqi leader Saddam Hussein in the same area, believes that “ISIS sleeper cells, with time, will decrease not only in their ability to run the insurgency, but also in their desire to do so.”

On the other side, between the ISIS members dispersed throughout the country and the poverty among the Arab Sunni population, insurgent group numbers will only continue to increase, as will their power. According to a former leader of an al Qaeda–linked group, Ansar Al Sunna, which operated in the Lake Hamrin area from 2004–2007 and later became part of ISIS in Iraq, “A lot of experienced people now in Mosul will try to get back here to continue their operations and, with time, interest in joining them will only increase among local youth.”

Whatever happens, BawaNuri and the Ansar Al Sunna leader do agree on one thing: the ball is now in the Iraqi government’s court, especially in its relations with the local Sunni population. Any gaps in security or reconciliation are sure to be exploited by surviving ISIS members who are ready and waiting to take advantage of the sectarian grievances and economic problems of the local population. Iraq's economic problems will be challenging to solve because of the current oil crisis, but the international community could help with humanitarian aid and development assistance. Meanwhile, it is entirely up to the local authorities and Baghdad to address the sectarian grievances that fuel the conflict. And on that score, there is little room for optimism.

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