The U.S.'s New anti-ISIS Partner in the Northeast
Does the Syrian government's takeover of SDF territory undermine or strengthen the counter-ISIS fight?
The Syrian government’s rapid takeover of territory previously controlled by the Syrian Democratic Forces (SDF) has resurfaced some long-standing concerns over the future of the counter-ISIS fight. For more than a decade, the SDF has served as the International Coalition’s main anti-ISIS partner on the ground. The Kurdish-run organization used this military and financial support to carve out a large area of control over a mostly Arab population. While this territory was seized by the SDF from ISIS, it had originally been controlled by locally-rooted Free Syrian Army and Islamist opposition factions. Many of these original revolutionary bodies from northeast Syria were displaced to the northwest when ISIS took over in 2014. Now they have returned as members of the new Syrian government’s military, security, and administrative structures.
Yet in the intervening years, the SDF and Coalition has built a large anti-ISIS apparatus, including counter-terrorism units, informant networks, and prisons holding more than 7,000 ISIS fighters. The collapse of the SDF has raised concerns among some western observers about the impact of this territorial change on the counter-ISIS fight. The Institute for the Study of War went so far as to claim that:
“The Syrian government cannot immediately replace the Syrian Democratic Forces as a reliable counter-ISIS partner in northeastern Syria. The SDF performs a range of functions that require well-developed networks and military infrastructure, which the Syrian government cannot build overnight. The SDF has excellent human intelligence networks that probably provide it with an excellent understanding of the ISIS threat it faces on the tactical level.”
This claim is heavily flawed, however, ignoring years of evidence from both the northeast and northwest about the tactics and successes of each side’s counter-ISIS campaigns. While it is true that the SDF has spent a decade receiving U.S. training, funding, and technical support, these resources do not directly translate into building effective clandestine networks. In the post-Caliphate era where ISIS operates as underground cells, it is these intelligence operations that underpin the ISIS fight.
Both the SDF and HTS have engaged in years of anti-ISIS campaigns within their respective territories. The divergent history of these campaigns suggests that Syria’s new government may actually be better suited to root out the persistent ISIS insurgency in formerly SDF-held areas.
SDF’s Failed Cooption
As the SDF rolled back ISIS in northeast Syria, it quickly encountered the huge challenge of building intelligence networks in Arab regions where the Kurdish-run organization had no history. Dareen Khalifa, a Senior Advisor at the International Crisis Group, has been visiting the northeast for more than a decade, meeting extensively with military, intelligence, and government officials as well as local communities. In 2019, she wrote about the SDF’s approach to gathering intelligence in Arab areas:
“This deficiency and its lack of local knowledge has led it to often rely on pre-existing structures that ISIS created to co-opt tribes as informants for the group’s security branches. Today, the SDF uses them for the exact same purpose. Thus, in Deir al-Zour some of the SDF’s local intermediaries, who once similarly cooperated with ISIS, today turn a profit by securing the release of ISIS followers in exchange for money and (not necessarily reliable) information.”
The SDF’s reliance on tribal networks and lack of local knowledge to vet any information it received resulted in persistent cases of false reporting – sometimes just to secure payment from informants’ handlers, other times as a means to settle local disputes. Khalifa writes that in March 2019 alone, SDF raids in Deir Ez Zor using inaccurate intelligence resulted in the murder of at least 111 innocent Arabs, with the SDF then having to pay blood money to many of the families and subsequently pause anti-ISIS operations to reduce tensions.
Despite these challenges, the SDF was able to initially identify and empower a few key Arab interlocutors in Deir Ez Zor in 2019. These men had the trust of the Arab community and the Kurdish military leaders. With their help, the SDF was able to initially secure the genuine cooperation of several key tribes in Deir Ez Zor. Yet continued security failures by the SDF eroded this fragile trust. ISIS cells were able to assassinate several crucial interlocutors early on, as well as other local Arabs working with both the civil and security institutions. Persistent insecurity resulted in locals increasingly wary of collaborating with a security force they did not believe was capable of protecting them.
In 2022, Dareen and I published a follow-up report on the ongoing counter-ISIS campaigns in northeastern Syria. Like her 2019 report, this one was again built on multiple field trips to Deir Ez Zor and Raqqa throughout 2020, 2021, and 2022 speaking with local security officials and activists. We found that growing perceptions of insecurity – fueled both by SDF failures and repeated claims by U.S. leaders of an imminent withdraw from the northeast – had, “discouraged the population from cooperating with the SDF’s counter-ISIS raids or providing intelligence on ISIS cells.”
ISIS operations in Deir Ez Zor in particular appeared to be specifically designed to undermine SDF intelligence gathering efforts by targeting anyone perceived as collaborating with local government and security forces. As early as 2021, SDF officers in Deir Ez Zor had told us that these attacks were successfully hindering their attempts to gather intelligence. This dynamic was further cemented by continued SDF raids targeting and killing innocent men based on wrong information. For its part, the SDF had also grown increasingly distrustful of any intelligence gathered by local networks in communities which had been major ISIS recruitment hubs, according to one senior intelligence officer. The lack of trust from both sides was, at its core, a result of the continued exclusion of Arabs from any real positions of power.
By late 2024, these dynamics had resulted in a substantial return of ISIS activity in the northeast, particularly in Deir Ez Zor. When I visited the area in September of that year, both security officials and locals claimed that ISIS recruitment, extortion, and ‘shadow governance’ had all increased in the governorate. According to one senior SDF official I spoke with, there were already twice as many ISIS attacks in the first six months of 2024 than in all of 2023, claiming that, “ISIS is now stronger than it was in 2019.” The situation was already unraveling before the collapse of the Assad regime.
HTS’s Northwest Campaign
Prior to the fall of Assad, HTS had run its own anti-ISIS campaign within its territorial holdings in northwest Syria. Unlike the SDF, HTS’s personnel were rooted within these communities. Even if locals had disputes with HTS leadership or its political and social policies, the group was able to tap into a huge breadth of influential individuals and veteran revolutionaries from every community to build trust at a local level. This would be the foundation from which HTS dismantled ISIS networks in its areas of control.
From mid-2017 through early 2019, ISIS cells conducted a robust insurgency across Idlib. ISIS relied on pre-existing networks that were then bolstered first by the Assad regime facilitating ISIS convoys into Idlib in 2017, then by targeted Russian airstrikes in 2019 against the main prison holding ISIS fighters which enabled hundreds to escape, and lastly by individual smuggling efforts from northeast Syria after 2019. HTS engaged in brutal battles against these ISIS fighters, particularly starting in May 2018 after it had consolidated military and political control over other opposition factions in Idlib. While eventually staving off the worst of the ISIS activity, clandestine ISIS activity renewed in 2020, triggering a new round of counter-ISIS operations.
In 2023, Dareen, Jerome Drevon, and I published a lengthy report on the history of HTS’s counter-Al Qaeda and counter-ISIS campaigns in northwest Syria, based on multiple trips to Idlib and interviews with intelligence and military officials there. The initial battles against ISIS coincided with the early establishment of new governing and security institutions in Idlib. A Ministry of Interior was established, and with it a new “General Security Force” which operated in close conjunction with HTS’s intelligence apparatus, led by the now-Minister of Interior Anas Khattab. This professionalization and creation of formal internal security forces played a large role in countering extremist networks. By the end of 2021, ISIS activity had been essentially eliminated in the northwest. 2022 saw at most three ISIS attacks, all unclaimed and which appeared to be lone-wolf attacks directed from outside Syria.
All of this success was built on sophisticated human intelligence networks. As one senior security official told us at the time, “We don’t have the technology or [surveillance] drones, as the Coalition does, to listen in and monitor ISIS members.” A veteran General Security officer now involved in operations against regime insurgents elaborated on this in a recent conversation with me:
“What helped us eliminate ISIS was our significant experience and the cooperation of the local population. ISIS was a danger to society, and the people of Idlib hated ISIS very much. Therefore, any information they received about ISIS was immediately shared with the security forces.”
Despite these successes, senior ISIS leaders were still able to hide in Idlib. ISIS’s first leader, Abu Bakr al-Baghdadi, was killed in a U.S. raid in Idlib in October 2019; his predecessor was similarly killed in Idlib in February 2022. The two operations were huge blows to HTS’s otherwise good record of counter-ISIS operations and underscored the serious gaps in the group’s capabilities at the time. Any overt ISIS activity could be exposed via local informant networks, but leaders simply sending physical messages via one or two trusted individuals were much more difficult to uncover.
A New Era of Collaboration
Following HTS’s overthrow of the Assad regime, it expanded these operations across former regime areas. Security forces suffered two serious failures when ISIS cells successfully conducted terror attacks against a church in Damascus in June and an Alawi mosque in Homs in December. Yet the government has prevented many more ISIS attacks throughout 2025 as well. In November 2025, Syria’s new government officially joined the U.S.-led anti-ISIS Coalition. However, according to Charles Lister, Director of MEI’s Syria Program, intelligence cooperation goes back several months earlier, already resulting in 11 joint operations, including two nation-wide arrest campaigns, and the disruption of at least 10 attempted mass casualty ISIS attacks.
The new government has proven, both during its time in Idlib and after the overthrow of Assad, its skill in establishing and utilizing human intelligence networks. Security forces have even been able to build effective informant networks in the heart of ex-regime Alawi communities, using these to routinely disrupt and arrest insurgent cells in Syria’s coast which had, in the first months after liberation, conducted extensive attacks against government forces. Damascus will now seek to do the same in the areas previously controlled by the SDF.
While the rapid change in territorial control inevitably provides ISIS room to maneuver, Damascus has been quick to fill the security void. The SDF withdrew from Deir Ez Zor in the early morning hours of January 18 under pressure from locals, with government military units already entering these towns by dawn. By the next morning the Ministry of Interior had established checkpoints across much of the area and announced the opening of police recruitment centers. At least some of these centers were already operating by January 20, a hopeful indicator that new local security forces will be formed quickly to support those brought in from outside.
Establishing new security and intelligence networks in Deir Ez Zor and Raqqa should not pose a challenge to Damascus. The new government has already spent the past year strengthening its ties to local Arab communities under SDF control, using these rebuilt networks to help expel SDF forces from half of its territory in less than 48 hours. Damascus’ established practice of security localization – appointing security, intelligence, and administrative officials within their own governorates or districts – will also ensure an immediate base level of local buy-in.
The General Security and General Intelligence officers now deployed to the recently liberated areas will be able to compound their local knowledge with years of experience combating ISIS, al-Qaeda, and more recently regime remnants. Rather than undermining established Coalition efforts, Damascus should be able to quickly leverage its extensive local networks in these areas to enhance intelligence gathering that, in conjunction with the Coalition’s resources, will amplify the counter-ISIS fight beyond what the SDF could do.