Defeated and Detained, Islamic State Still Poses Extremism Threat

An eighty-five-nation coalition celebrated the defeat of the self-proclaimed Islamic State in Iraq and Syria, also known as ISIS, in 2019, but the conundrum of what to do with an unprecedented number of captured militants and their families could trouble the world for years to come. Today, detained Islamic State fighters in northeastern Syria reportedly constitute the world’s largest concentration of terrorists, and tens of thousands of people with suspected links to the organization are languishing in Syrian displacement camps. With governments reluctant to repatriate remnants of the terrorist group, the situation raises dire security, legal, and human rights concerns.

What is the status of the Islamic State in Syria?

At its strongest in 2014, the Islamic State controlled at least a third of both Iraq and Syria, the group’s core area of operations. By early 2019, the last territory under its control had fallen to the U.S.-backed Syrian Democratic Forces (SDF), the military of the autonomous Kurdish government that controls northeastern Syria.

Today, the Islamic State possesses a scant 2,500–3,500 fighters across Iraq and Syria, according to UN estimates, and is believed incapable of mounting large-scale attacks [PDF] in either country. Instead, its threat has been overshadowed by that of its affiliates in Afghanistan and parts of Africa. Experts say the group aims to rebuild by liberating the large numbers of its members detained in Syria and radicalizing residents of SDF-run facilities for refugees and internally displaced persons (IDPs). Its most notable attempt, in January 2022, freed dozens of prisoners before the combined forces of the United States, the United Kingdom (UK), and the SDF secured the facility.

What’s the situation for Islamic State–linked detainees and IDPs in northeastern Syria?

As of January, some sixty-five thousand people thought to have direct or indirect links to the Islamic State were being held in an array of facilities run by the SDF. Over fifty thousand of them, the vast majority of them women and children, are crowded into the most infamous displacement camp, al-Hol.

The displaced detainees are a mix of those who profess loyalty to the Islamic State, those who unwillingly encountered the organization when their husbands and fathers joined, and those who happened to live in areas seized by the Islamic State. The amount who actually subscribe to the group’s ideology is unclear but not small, experts say, and extremist leanings remain strongest among residents not from Iraq or Syria.

The United States maintains some nine hundred residual troops in Syria to perform counterterrorism operations and provide some training and security assistance to the SDF. Yet, SDF-run facilities are notoriously insecure, poorly resourced, prone to disease outbreaks, and ill-equipped for the area’s extreme temperatures. Many children have missed years of school, and young boys are often separated from their mothers. SDF officials say they do this because mothers try to radicalize their sons and force them to have sex with Islamic State women to grow the group’s numbers. The United Nations and rights groups have condemned the family separations as dangerous and unlawful, and some experts have questioned the veracity of the SDF’s claims.

What’s the debate around these facilities?

Most experts see them as targets for Islamic State raids, incubators for future extremists, and an overall untenable detention system, particularly given the SDF’s limited resources for operating them. Like the United Nations, U.S. officials assert that “repatriation, rehabilitation, reintegration, and—where appropriate—prosecution and incarceration” of the facilities’ residents by their home countries will prevent the resurgence of the Islamic State. Yet, international law doesn’t require countries of origin to repatriate their nationals in the Syrian facilities. And thus far, many countries have spurned repatriation or opted to only bring home some women and young children. Some, such as Australia, Ireland, and the UK, have opted to revoke the citizenship of some dual nationals rather than take them back. 

Countries cite multiple barriers to repatriation:

Legal obstacles. Many home countries lack the political will and resources to investigate and prosecute returnees who are suspected of committing terrorism-related offenses. Additionally, evidence of Islamic State–linked offenses can be difficult to collect and considered sensitive intelligence that can’t be used in most courts.

Engrained extremism. Governments worry that if they repatriate some nationals and fail to successfully prosecute or deradicalize them, those returnees could become security threats, given their exposure to extremist rhetoric.

Reintegration challenges. Most returnees will need extensive support to effectively reenter society. This can include job training, psychological counseling, help attaining civil documents, and housing assistance. Returnees may also find that their communities don’t want them back.

Syria’s divisions. Civil war has split Syria into government- and opposition-held territories. Most of the SDF facilities’ twelve thousand Syrian residents hail from government-held areas, and there are no formal mechanisms for their return. Meanwhile, countries are wary of negotiating with nonstate actors such as the Kurdish administration, which has reportedly asked Western countries to recognize its government in exchange for some returnees. It also has links to the Kurdistan Workers’ Party (PKK), which the United States, Turkey, and the European Union consider a terrorist organization.

Various governments have proposed alternatives to repatriation, such as legal mechanisms to try detainees in Iraq. The Kurdish administration and some U.S. lawmakers also have suggested establishing an international tribunal for Islamic State members, similar to those that prosecuted war criminals in Rwanda and the former Yugoslavia. “There has to be some international body that adjudicates this on a case-by-case, individual basis,” says CFR counterterrorism expert Bruce Hoffman. “[The evidence] is going to be incomplete. That’s the nature of these kinds of messy nonstate wars. But that’s the only solution that I see.”

What’s next for the detainees?

Without a surge in repatriations, they could languish in Syria indefinitely without adjudication. Some analysts compare the situation to the U.S. detention camp in Guantanamo Bay, Cuba, which has held many alleged terrorists and their supporters in legal limbo for more than twenty years. The Kurdish administration announced in June that it will begin trying thousands of foreign fighters, but no trials have been announced so far, and critics say the administration lacks the jurisdiction to hold any.

As long as the Syrian facilities remain open, they will be targets for raids by the Islamic State, especially if U.S. troops withdraw. They could also become staging grounds for attacks. “Either the very unsatisfactory status quo is going to continue, or I think we'll see, potentially, acts of violence that may be traced back to the camps. And maybe that’s the only way that will prompt action,” Hoffman says.

Will Merrow and Michael Bricknell contributed to the graphics in this In Brief.

Correction: This In Brief previously referred to the SDF as the “Syrian Defense Forces.” This error was corrected on July 31, 2023.