April 23, 2026.

Abstract:

This study analyzes the growing problem of foreign fighters in Syria and assesses the challenges they pose to U.S. counterterrorism objectives, regional stability, and the prevention of an ISIS resurgence. It evaluates how the integration of jihadist factions into Syrian state institutions contributes to sectarian violence, institutional fragmentation, and opportunities for extremist recruitment. The study further compares alternative U.S. policy responses, including the status quo, repatriation, and disarmament, demobilization, and reintegration (DDR) programs, concluding that DDR offers the most effective long-term strategy for managing foreign fighters and stabilizing Syria.

The Problem

The Syrian Civil War began in 2011 as an uprising against President Bashar al-Assad and quickly evolved into a prolonged conflict involving state forces, rebel groups, and transnational jihadist organizations. After fourteen years of war, resulting in over 400,000 deaths and the displacement of 13 million people, the jihadist group Hay’at Tahrir al-Sham overthrew Assad in December 2024, with its leader Ahmed al-Sharaa seizing power in Damascus.[i] A defining feature of this conflict was the influx of foreign fighters from countries like Tunisia, Saudi Arabia, Russia, and several Balkan, Caucasus, and Central Asian states, many of whom joined groups like the Islamic State and Jabhat al-Nusra, HTS’s predecessor.[ii]

The United Nations Security Council estimates that approximately 5,000 foreign fighters remain in Syria, with around 3,500 integrated into Syrian security forces, particularly within the 84^th Brigade in Latakia.[iii] These units include militant factions such as the Uzbek Jihadist Union and the Turkistan Islamic Party, whose leader, Abdul Haq al Turkistani, sits on al-Qaeda’s shura council.[iv] Their presence within state institutions is especially concerning, because the TIP and similar groups have been linked to sectarian violence, including the March 2025 Alawite massacre in Latakia, which killed more than 1,000 civilians.[v] Foreign fighters played a critical role in helping Ahmed al-Sharaa overthrow Assad, but their continued presence in post-conflict Syria poses a significant challenge to U.S. interests by undermining counterterrorism efforts and regional stability.[vi]

These factions, including both remaining Islamic State elements and those integrated into government forces, present a direct security challenge by embedding ideological extremists within Syrian institutions. [vii] As a result, these actors retain the capacity to “plot or inspire external terrorist operations” against the U.S. and its allies. [viii] In addition, divisions between Syria’s leadership and hardline jihadist factions further create opportunities for defections to the Islamic State, which maintains an estimated force of 3,000 fighters in Syria and Iraq.[ix] ISIS has actively pursued propaganda and recruitment campaigns aimed at targeting dissatisfied fighters within HTS-aligned units, while allegedly maintaining sleeper cells embedded within the Syrian security apparatus.[x]

At the same time, ideological fractures have emerged between foreign fighter factions and Ahmed al-Sharaa following Assad’s fall, with some labeling him a “sell out,” and participating in coup and assassination attempts against his government.[xi] The defection of experienced fighters and ideological extremists would strengthen ISIS’s capabilities by enhancing its ability to conduct attacks, rebuild influence and control, and potentially coordinate external attacks against Western targets.[xii] For example, the ISIS-inspired attack that killed two U.S. National Guardsmen in Palmyra highlights the risks associated with integrating or overlooking extremist actors within Syrian security forces.[xiii] Additionally, the continued operation of both domestic and foreign jihadist networks alongside ISIS undermines U.S. objectives of stabilizing Syria and preventing its reemergence as a safe haven for terrorists.[xiv]

Beyond the threat posed by ISIS, instability created by these factors increases the likelihood of renewed conflict in Syria, providing strategic openings for Iran to engage indirectly through proxy militias, similar to how the Islamic Republic did with Hezbollah under Assad. Such instability further complicates U.S. efforts to maintain regional balance and contain extremist threats.[xv] Therefore, foreign fighters and ISIS pose a direct threat to the U.S. and undermine long-term objectives of stability, counterterrorism, and Iranian containment in Syria.

U.S. Objectives in Syria

In response to this problem, the primary objective of the United States is to prevent the resurgence of ISIS and limit the threat posed by foreign fighter networks. Officials within the Trump administration have emphasized counterterrorism as the central security priority in Syria, focusing on denying terrorist groups safe havens and limiting their ability to exploit instability while advancing the broader goal of promoting a stable Syrian state.[xvi] In May 2025, President Donald Trump met with Ahmed al-Sharaa in Riyadh, where he urged Syria to “tell all foreign terrorists to leave Syria [and] help the United States prevent the resurgence of ISIS.”[xvii] Trump further emphasized that Syria should assume responsibility for ISIS detention facilities in northeastern Syria, signaling a shift away from reliance on the Syrian Democratic Forces and toward Damascus as a counterterrorism partner.[xviii]

These goals have been reinforced through conditional U.S. engagement. In March 2025, U.S. officials provided the Syrian government with a list of demands tied to sanctions relief, including a commitment to contain ISIS, expel foreign fighters, and prevent extremists from entering institutions or leadership positions.[xix] Additionally, U.S. policy aims to prohibit Iran from reestablishing a “foothold in the country,” as instability and Islamic militancy create opportunities for Iranian proxy expansion.[xx]

More broadly, the United States seeks to promote a stable Syrian state capable of cooperating with international counterterrorism efforts and regional security initiatives, including normalization efforts. As part of this objective, Trump instructed Sharaa to “sign onto the Abraham accords with Israel.”[xxi] During the Riyadh meeting, Trump also emphasized that the U.S. was lifting sanctions “in order to give them a chance at greatness,” expressing hope that Sharaa would “succeed in stabilizing the country and keeping peace.”[xxii] A more stable Syria would reduce the likelihood of recurring violence and the emergence of ungoverned spaces that extremist organizations such as ISIS have historically exploited.

Taken together, these objectives aim to build a strategic relationship with Damascus while also advancing U.S. interests and security goals in Syria, reflecting objectives centered on counterterrorism, Iranian containment, and stabilization.

Policy Options

The U.S. status quo in Syria reflects a cautious and conditional engagement with Damascus, aimed at containing the Islamic State and managing the risks posed by foreign fighters. Following the May 2025 waiver of Caesar Act sanctions, the United States signaled a willingness to engage, including reconsidering terrorist designations.[xxiii] Additionally, the list of demands presented to Syria by U.S. officials in March 2025 required that Damascus ensure that foreign fighters are not appointed to senior government or military leadership positions.[xxiv] While twelve foreign fighters have been appointed to high-ranking positions within the Syrian Ministry of Defense, no further promotions have been made since December 2024, suggesting partial compliance with U.S. demands.[xxv]

At the same time, U.S. policy emphasizes limited involvement. Under the Trump administration, the U.S. has provided no direct funding to the Syrian government while continuing financial support for the Syrian Democratic Forces. Despite this limited engagement, Washington has intervened when necessary, including facilitating the transfer of up to 7,000 ISIS detainees to Iraq during clashes between Syrian forces and the SDF.[xxvi] After initial pressure on Syria to expel foreign fighters, U.S. policy has shifted toward conditional acceptance of their integration. U.S. Special Envoy Tom Barrack stated that Washington has reached “an understanding with transparency” on the issue, suggesting that the U.S. is willing to tolerate the integration of foreign fighters.[xxvii] The status quo reflects a strategy focused on managing the threats posed by these groups while also limiting direct U.S. involvement.

An alternative policy would involve the United States actively promoting the repatriation and prosecution of foreign fighters to their home countries. Under this approach, militants currently operating in Syria, those embedded in Syrian security forces, and ISIS detainees in prison camps would be returned to their home states to be prosecuted, monitored, and reintegrated through state-led programs. The U.S. would play a central role in coordinating this effort by using diplomatic pressure, intelligence sharing, and conditional aid to encourage Syria and foreign governments to cooperate. This policy initiative could include utilizing sanctions relief to pressure Damascus to cooperate in identifying and transferring foreign fighters while also pressuring allied states to accept returnees.[xxviii]

Repatriation and prosecution demonstrate feasibility, particularly in Central Asia. Kazakhstan’s Operation Zhusan, successfully repatriated over 650 individuals between 2019 and 2021, including former ISIS fighters and their families.[xxix] The repatriation process occurred through coordinated efforts involving security services, diplomacy, and reintegration programs. Similarly, Uzbekistan has repatriated over 500 people affiliated with ISIS, showing that repatriation is an obtainable alternative to address extremist threats. By returning foreign fighters to their home states, governments can prosecute, monitor, and contain returnees, rather than leaving these individuals armed in a conflict-prone environment.

A third policy option would involve the U.S. supporting a structured disarmament, demobilization, and reintegration program that targets foreign fighters in Syria. Under this policy, foreign fighter units, particularly those already integrated into Syrian security forces, would be disarmed, removed from the military, and transitioned into civilian life. Historically, DDR programs have been implemented by U.N.-supported national DDR commissions and operate in three phases: disarmament (weapons collection), demobilization (removal from armed groups), and reintegration (return to society through employment, education, and monitoring).[xxx]

The United States would support and oversee DDR by leveraging diplomatic pressure, conditional sanctions relief, security cooperation to encourage Syrian participation. The U.S. could also tie normalization efforts and economic incentives to set DDR goals and benchmarks, such as the removal of certain militant factions from military structures and leadership positions. Successful implementation, however, would require substantial resources to create and provide employment opportunities for former combatants. Syria’s estimated $200 billion reconstruction requirement would make these incentives difficult to fund.[xxxi] Yet, DDR offers a structured and tested approach to reducing the long-term threat posed by foreign fighters by transforming them from combatants into monitored civilians. DDR’s success ultimately depends on sustained international support, coordination, and Syrian compliance.

Evaluation of Policy Options

            The current U.S. approach offers limited efficacy in addressing both the foreign fighter problem and the resurgence of ISIS. While conditional engagement has enabled some cooperation with the Syrian government, such as joint counterterrorism operations, it has not reduced the presence of foreign fighters in Syria. Approximately 3,500 foreign fighters remain integrated into Syrian military structures, with some maintaining ideological ties to extremist networks such as al-Qaeda.[xxxii] This limits the effectiveness of the status quo in achieving U.S. goals by failing to directly address the foreign fighter threat.

Regarding ISIS, the status quo has achieved only partial containment. ISIS maintains an estimated force of 3,000 fighters in Syria and Iraq and continues to exploit instability by recruiting disillusioned fighters and infiltrating Syrian security structures.[xxxiii] Although U.S.-coordinated counterterrorism operations have successfully targeted ISIS infrastructure, the group has demonstrated resilience and adaptability, indicating that the current U.S. policy in Syria is insufficient in preventing a long-term resurgence.

            The status quo also generates high externalities and negative consequences regardless of whether it succeeds. The integration of foreign fighters into security forces has already contributed to sectarian violence, including the March 2025 Alawite massacre in the coastal region of Latakia, which resulted in over 1,000 civilian deaths, as well as clashes with Druze militias.[xxxiv] Additionally, the continued presence of semi-autonomous militant units, such as the Turkistan Islamic Party whose central branch operates in Afghanistan, contributes to fragmentation within the Syrian military, increasing the risk of internal clashes, coup attempts, and institutional instability. These conditions also create opportunities for extremist infiltration into state institutions. The U.N. Security Council has warned that ISIS may have already infiltrated Syrian security structures, increasing the likelihood that Syria may reemerge as a safe haven for terrorist organizations.

            The primary advantage of the status quo is its low financial cost. The U.S. has provided no direct funding to the Syrian government while allocating approximately $130 million to partner forces such as the Syrian Democratic Forces in fiscal year 2026.[xxxv] Although total U.S. humanitarian aid to Syria has exceeded $17.8 billion since 2011, current financial commitments remain limited compared to previous financial initiatives in Syria.[xxxvi] As a result, the status quo is financially sustainable but comes at the expense of long-term strategic effectiveness.

            Repatriation offers a direct approach to addressing the foreign fighter problem by removing individuals from Syria and placing them under the jurisdiction of their home countries, making it moderately effective. This policy enables prosecution, surveillance, and long-term monitoring, effectively reducing the risk posed by keeping them embedded within state institutions and unstable environments. Evidence from Central Asia demonstrates that this approach is possible, with Kazakhstan and Uzbekistan already implementing repatriation and prosecution programs to return ISIS-affiliated individuals.[xxxvii]

Applied to ISIS, however, repatriation presents mixed effectiveness. Removing foreign fighters from Syria reduces the available recruitment pool for the Islamic State, however, returnees may pose significant security risks in their home countries. Studies by jihadism expert Thomas Hegghammer suggest that one in 360 returnees have engaged in terrorist activity, yielding a low probability but high consequence risk.[xxxviii] Furthermore, returnees are often more lethal due to training and operational experience, as some may radicalize others upon return.[xxxix] However, repatriation enables monitoring through surveillance and investigation, an option which is unavailable while they remain in Syria.

            Repatriation produces several moderate-to-high externalities despite success. This policy shifts the burden of managing these individuals from Syria to the international community, placing strain on domestic legal systems in home countries, intelligence agencies, and reintegration programs. Furthermore, many states lack the legal framework or resources necessary to repatriate and prosecute foreign fighters effectively upon return, with each state having varying program rules and practices. [xl] Additionally, repatriation often generates domestic political backlash, as public opinion in many Western states strongly opposes the return of ISIS fighters. For example, 77 percent of surveyed individuals in the United Kingdom opposed allowing foreign fighters to return. [xli]

            Repatriation is associated with high administrative, legal, and long-term monitoring costs. Governments must fund identification, transportation, prosecution, and reintegration programs, all of which require coordination across multiple agencies. Evidence collection from active conflict zones is especially difficult and costly because prosecutors must obtain evidence from Syria for use in domestic courts.[xlii] Additionally, deradicalization and reintegration programs require sustained funding to support social services, education, and employment opportunities.

            DDR offers an effective approach to addressing the foreign fighter problem by directly targeting their role within Syrian security structures, with a moderately high level of efficacy. By disarming and demobilizing foreign fighters, they are removed from military positions while keeping them in a controlled and contained environment. Evidence from U.N. disarmament, demobilization, and reintegration programs suggest that these initiatives reduce the likelihood of conflict recurrence, particularly given that nearly half of civil wars relapse within five years due to no effective post-conflict program.[xliii]

Applied to ISIS, DDR has conditional efficacy. By providing pathways for conflict resolution, DDR can reduce incentives for fighters to defect to ISIS by providing economic incentives for individuals to leave extremist groups. However, success depends heavily on economic conditions and political stability, as without sufficient support, demobilized fighters may rejoin extremist organizations, limiting the policy’s effectiveness at achieving U.S. goals.

DDR also introduces several externalities regardless of outcome. Efforts to disarm foreign fighters may provoke resistance from hardline factions, potentially triggering violence against the Syrian government. Attempted coups, assassinations, and clashes between foreign fighter groups and state forces highlight that such measures could further escalate tensions. For example, more than ten members of jihadist group Ansar Al-Islam were arrested for plotting a coup, with five foiled assassination attempts against President Sharaa. [xliv] Furthermore, DDR programs may unintentionally legitimize former extremists by reintegrating them into a society while not being fully rehabilitated, raising concerns about long-term radicalization and reintegration.

            Despite its advantages, DDR is one of the most expensive policy options for handling foreign fighters in Syria. U.N. DDR programs have historically required millions of dollars in annual funding, with individual programs costing approximately $6-7 million per year. In 2019 alone, the U.N. DDR budget was $34 million across five different programs.[xlv] In the Syrian context, costs would likely be significantly higher due to the country’s $200 billion reconstruction needs and the scale of reintegration required.[xlvi] DDR would also require sustained international funding and coordination among the United States, the United Nations, and the Syrian government, making implementation financially demanding.

Policy Recommendation

            Among the three policy options, a structured disarmament, demobilization, and reintegration program offers the most effective strategy for achieving both short-term and long-term U.S. goals in Syria. While each policy has significant tradeoffs in terms of efficacy, externalities, and cost, DDR offers the most balanced and well-established approach to addressing both the foreign fighter threat and the risk of ISIS resurgence, while also aligning with stabilization and counterterrorism objectives.

            In terms of efficacy, DDR outperforms the status quo and repatriation policies by directly targeting the role and influence of foreign fighters within the Syrian security apparatus. In contrast, the status quo allows approximately 3,500 foreign fighters to remain in military structures, while DDR actively removes these individuals from positions of power and disarms them, reducing their ability to carry out violence and jeopardize stability. Consequently, DDR is more effective than current U.S. policy, which has achieved only limited success in reducing the influence of foreign fighter factions and leaders in Syria, ultimately contributing to continued sectarian violence and clashes between government forces and hardline militant factions.

Repatriation removes fighters from Syria but disperses the threat internationally. DDR instead contains these dangerous and radicalized individuals within a controlled environment where they can be monitored, rehabilitated, and reintegrated without transferring the security burden to other states. Applied to ISIS, DDR also demonstrates stronger efficacy than the first two options. While repatriation reduces the recruitment pool for ISIS in Syria, it relocates the threat to other regions, where returnees may radicalize others and conduct attacks in their home countries.[xlvii] In contrast, the status quo has largely contained ISIS rather than weakening the conditions that enable its resurgence. DDR reduces the incentives for individuals to defect to ISIS by providing pathways for disengagement, such as employment and reintegration programs. Although the efficacy and success rate depend on sufficient economic support, DDR is the only policy that reduces both supply of foreign fighters and the conditions that enable ISIS recruitment.

            Regarding externalities, DDR presents moderate risks but is preferable to the alternatives, especially the status quo. Current U.S. policy in Syria produces high negative externalities, including sectarian violence, military fragmentation, and the potential reemergence of ungoverned territory, providing safe havens for terrorists. On the other hand, while repatriation is effective at removing individuals from conflict zones in Syria, it generates moderate to high externalities by shifting the burden and risk to other states. DDR does carry risks, particularly the possibility of resistance from hardline jihadist units integrated within Syrian forces. However, these risks remain more manageable and contained compared to those posed by repatriation.

            Although DDR carries the highest cost of the three policies, its strategic benefits outweigh the financial cost. Successful implementation requires substantial funding, coordination, support, and time, often costing millions of dollars annually. Furthermore, DDR in Syria would likely be more expensive due to the amount of destruction and reconstruction required. However, the status quo, while low in cost, fails to achieve strategic long-term U.S. objectives. Repatriation also involves significant legal, administrative, and monitoring duties across multiple states, with active conflict zones slowing the process of investigation. In contrast, DDR presents an investment aimed at addressing the root causes of conflict and instability while also eliminating long-term security threats. Therefore, the higher cost of DDR is justified by its ability to produce more effective outcomes. Rather than representing simply a security expenditure, it is vital that DDR initiatives in Syria be viewed as a long-term investment aimed at reducing instability, preventing the resurgence of extremist elements, and strengthening regional security.

            Ultimately, DDR provides the most comprehensive and sustainable solution to managing foreign fighters in Syria in a way that best achieves U.S. goals in Syria. By directly reducing the presence and power of foreign fighters, limiting opportunities for ISIS recruitment and resurgence, and supporting long-term stabilization efforts, DDR aligns most closely with U.S. counterterrorism policy in Syria, providing the strongest foundation for lasting security and regional stability.

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[i]Mara Karlin, “Shaping the New Syria,” published February 12, 2026, Brookings Institution, Shaping the new Syria | Brookings.

[ii] Efraim Benmelech and Esteban F. Klor, “What Explains the Flow of Foreign Fighters to ISIS?” April 2016, What Explains the Flow of Foreign Fighters to ISIS? | NBER.

[iii] United Nations Security Council,  36th report of the Analytical Support and Sanctions Monitoring Team concerning Islamic State in Iraq and the Levant (Da’esh), Al-Qaida and Associated Individuals, Groups, Undertakings and Entities, July 24, 2025.Letter dated 21 July 2025 from the Chair of the Security Council Committee pursuant to resolutions 1267 (1999), 1989 (2011) and 2253 (2015) concerning Islamic State in Iraq and the Levant (Da’esh), Al-Qaida and associated individuals, groups, undertakings and entities addressed to the President of the Security Council

[iv] Bill Roggio, “Hayat Tahrir al Sham’s Terror Network in Syria,” Long War Journal, December 12, 2024, Foundation for Defense of Democracies, Hayat Tahrir al Sham’s terror network in Syria – FDD’s Long War Journal.

[v] Christopher M. Blanchard, Syria: Transition and U.S. Policy, Congressional Research Service, February 26, 2026, Syria: Transition and U.S. Policy.

[vi]Adrian Shtuni, “From Insurgency to Statecraft: Al-Sharaa and Syria’s Foreign Fighters Test,” CTC Sentinel 19, no. 2 (February 2026), Combating Terrorism Center at West Point, From Insurgency to Statecraft: Al-Sharaa and Syria’s Foreign Fighters Test – Combating Terrorism Center at West Point.

[vii] Christopher M. Blanchard, Syria: Transition and U.S. Policy, Congressional Research Service, February 26, 2026, Syria: Transition and U.S. Policy.

[viii] U.S. Department of State, Country Reports on Terrorism 2023 (Washington, DC: Bureau of Counterterrorism, 2024) Country Reports on Terrorism 2023 – United States Department of State.

[ix] Loveday Morris and Mustafa Salim, “Iraqi Spy Chief Warns of Reemerging Threat from ISIS as Its Ranks Swell,” The Washington Post, January 27, 2026, Iraqi spy chief warns of reemerging threat from ISIS as its ranks swell – University of Mary Washington.

[x] Kelly Kassis, “Islamic State Containment Is Collapsing in Syria,” War on the Rocks, March 19, 2026, Islamic State Containment Is Collapsing in Syria.

[xi] Adrian Shtuni, “From Insurgency to Statecraft: Al-Sharaa and Syria’s Foreign Fighters Test,” CTC Sentinel 19, no. 2 (February 2026), Combating Terrorism Center at West Point, From Insurgency to Statecraft: Al-Sharaa and Syria’s Foreign Fighters Test – Combating Terrorism Center at West Point.

[xii] U.S. Department of State, Country Reports on Terrorism 2023 (Washington, DC: Bureau of Counterterrorism, 2024) Country Reports on Terrorism 2023 – United States Department of State.

[xiii] Seth Frantzman, “Syria Investigates Deadly Attack on US Forces, US Names 2 National Guard Soldiers as Victims,” Long War Journal, December 15, 2025, Foundation for Defense of Democracies, Syria investigates deadly attack on US forces, US names 2 National Guard soldiers as victims – FDD’s Long War Journal.

[xiv]The White House, “Providing for the Revocation of Syria Sanctions,” executive order, June 30, 2025, Providing for the Revocation of Syria Sanctions – The White House.

[xv] Assaf Orion et al., “The Wartime Role of Iran’s ‘Axis’: Countering Proxy and Terrorist Threats,” March 5, 2026, The Washington Institute for Near East Policy, The Wartime Role of Iran’s “Axis”: Countering Proxy and Terrorist Threats | The Washington Institute.

[xvi] The White House, “Fact Sheet: President Donald J. Trump Provides for the Revocation of Syria Sanctions,” June 30, 2025, Fact Sheet: President Donald J. Trump Provides for the Revocation of Syria Sanctions – The White House.

[xvii] Ahmad Sharawi, “Trump Presses Sharaa on Foreign Fighters as Jihadists Rise in Syria’s New Army,” Long War Journal, May 16, 2025, Foundation for Defense of Democracies, Trump presses Sharaa on foreign fighters as jihadists rise in Syria’s new army.

[xviii] Ahmad Sharawi, “Trump Presses Sharaa on Foreign Fighters as Jihadists Rise in Syria’s New Army,” Long War Journal, May 16, 2025, Foundation for Defense of Democracies, Trump presses Sharaa on foreign fighters as jihadists rise in Syria’s new army.

[xix] Dale Sprusansky, “U.S. Open to Engaging Syria, Submits List of Demands,” Washington Report on Middle East Affairs 44, no. 4 (2025): 79–80, U.S. Open to Engaging Syria, Submits List of Demands – University of Mary Washington.

[xx] Dale Sprusansky, “U.S. Open to Engaging Syria, Submits List of Demands,” Washington Report on Middle East Affairs 44, no. 4 (2025): 79–80, U.S. Open to Engaging Syria, Submits List of Demands – University of Mary Washington.

[xxi]Gram Slattery, Pesha Magid, and Andrew Mills, “Trump Meets Syrian President, Urges Him to Establish Ties with Israel,” Reuters, May 14, 2025, Trump meets Syrian president, urges him to establish ties with Israel | Reuters.

[xxii] Trump Bets on Syria’s Former Jihadist; The President Will Remove All U.S. Sanctions against the New Damascus Regime,” The Wall Street Journal, 2025, Trump Bets on Syria’s Former Jihadist; The President will remove all U.S. sanctions against the new Damascus regime – University of Mary Washington.

[xxiii] The White House, “Fact Sheet: President Donald J. Trump Provides for the Revocation of Syria Sanctions,” June 30, 2025, Fact Sheet: President Donald J. Trump Provides for the Revocation of Syria Sanctions – The White House.

[xxiv] Ahmad Sharawi, “Trump Presses Sharaa on Foreign Fighters as Jihadists Rise in Syria’s New Army,” Long War Journal, May 16, 2025, Foundation for Defense of Democracies, Trump presses Sharaa on foreign fighters as jihadists rise in Syria’s new army.

[xxv] Adrian Shtuni, “From Insurgency to Statecraft: Al-Sharaa and Syria’s Foreign Fighters Test,” CTC Sentinel 19, no. 2 (February 2026), Combating Terrorism Center at West Point, From Insurgency to Statecraft: Al-Sharaa and Syria’s Foreign Fighters Test – Combating Terrorism Center at West Point.

[xxvi] Seth Frantzman, “US Withdraws from Iraqi Airbase, Transfers Islamic State Detainees from Syria to Iraq,” Long War Journal, January 21, 2026, Foundation for Defense of Democracies, US withdraws from Iraqi airbase, transfers Islamic State detainees from Syria to Iraq – FDD’s Long War Journal.

[xxvii] U.S. Department of State, Country Reports on Terrorism 2023 (Washington, DC: Bureau of Counterterrorism, 2024) Country Reports on Terrorism 2023 – United States Department of State.

[xxviii] Adam Hoffman and Marta Furlan, Challenges Posed by Returning Foreign Fighters (Washington, DC: Program on Extremism at George Washington University, March 2020), CHALLENGES POSED BY RETURNING FOREIGN FIGHTERS.

[xxix] William B. Farrell et al., Processes of Reintegrating Central Asian Returnees from Syria and Iraq, Special Report no. 498 (Washington, DC: United States Institute of Peace, July 2021), sr_498-processes_of_reintegrating_central_asian_returnees_from_syria_and_iraq.pdf.

[xxx] United Nations, “Disarmament, Demobilization and Reintegration,” April 20, 2026, Disarmament, demobilization and reintegration | UN Peacekeeping.

[xxxi] Mara Karlin, “Shaping the New Syria,” published February 12, 2026, Brookings Institution, Shaping the new Syria | Brookings.

[xxxii] United Nations Security Council,  36th report of the Analytical Support and Sanctions Monitoring Team concerning Islamic State in Iraq and the Levant (Da’esh), Al-Qaida and Associated Individuals, Groups, Undertakings and Entities, July 24, 2025.Letter dated 21 July 2025 from the Chair of the Security Council Committee pursuant to resolutions 1267 (1999), 1989 (2011) and 2253 (2015) concerning Islamic State in Iraq and the Levant (Da’esh), Al-Qaida and associated individuals, groups, undertakings and entities addressed to the President of the Security Council

[xxxiii] Bill Roggio, “Hayat Tahrir al Sham’s Terror Network in Syria,” Long War Journal, December 12, 2024, Foundation for Defense of Democracies, Hayat Tahrir al Sham’s terror network in Syria – FDD’s Long War Journal.

[xxxiv] Christopher M. Blanchard, Syria: Transition and U.S. Policy, Congressional Research Service, February 26, 2026, Syria: Transition and U.S. Policy.

[xxxv] U.S. Plans to Fold SDF into Syrian Army—So Why Fund It in 2026?” The National Context, July 6, 2025, U.S. Plans to Fold SDF into Syrian Army—So Why Fund It in 2026? – The National Context.

[xxxvi] U.S. Department of State, “United States Announces Additional Humanitarian Assistance for Syria,” May 27, 2024, United States Announces Additional Humanitarian Assistance for Syria – United States Department of State.

[xxxvii] Human Rights Watch, “Tunisia: Six Orphans Brought Home from Libya,” news release, February 6, 2020, Tunisia: Six Orphans Brought Home from Libya | Human Rights Watch.

[xxxviii] Thomas Hegghammer and Petter Nesser, “Assessing the Islamic State’s Commitment to Attacking the West,” Perspectives on Terrorism 9, no. 4 (2015): 14–30, Assessing the Islamic State’s Commitment to Attacking the West – University of Mary Washington.

[xxxix] Thomas Hegghammer, “Should I Stay or Should I Go? Explaining Variation in Western Jihadists’ Choice between Domestic and Foreign Fighting,” American Political Science Review 107, no. 1 (2013): 1–15, https://doi.org/10.1017/S0003055412000615.

[xl] William B. Farrell, Rustam Burnashev, Rustam Azizi, and Bakhtiyar Babadjanov, Processes of Reintegrating Central Asian Returnees from Syria and Iraq, Special Report no. 498 (Washington, DC: United States Institute of Peace, July 2021), sr_498-processes_of_reintegrating_central_asian_returnees_from_syria_and_iraq.pdf.

[xli] Adam Hoffman and Marta Furlan, Challenges Posed by Returning Foreign Fighters (Washington, DC: Program on Extremism at George Washington University, March 2020), CHALLENGES POSED BY RETURNING FOREIGN FIGHTERS.

[xlii] Adam Hoffman and Marta Furlan, Challenges Posed by Returning Foreign Fighters (Washington, DC: Program on Extremism at George Washington University, March 2020), CHALLENGES POSED BY RETURNING FOREIGN FIGHTERS.

[xliii] Julia Palik, “Costly Concessions: Insights From 78 Disarmament, Demobilization, and Reintegration (DDR) Provisions in Peace Agreements,” Global Policy 16, no. 5 (2025): 921–33, https://doi.org/10.1111/1758-5899.70040.

[xliv] Adrian Shtuni, “From Insurgency to Statecraft: Al-Sharaa and Syria’s Foreign Fighters Test,” CTC Sentinel 19, no. 2 (February 2026), Combating Terrorism Center at West Point, From Insurgency to Statecraft: Al-Sharaa and Syria’s Foreign Fighters Test – Combating Terrorism Center at West Point.

[xlv] Julia Palik, “Costly Concessions: Insights From 78 Disarmament, Demobilization, and Reintegration (DDR) Provisions in Peace Agreements,” Global Policy 16, no. 5 (2025): 921–33, https://doi.org/10.1111/1758-5899.70040.

[xlvi] Mara Karlin, “Shaping the New Syria,” published February 12, 2026, Brookings Institution, Shaping the new Syria | Brookings.

[xlvii] Thomas Hegghammer and Petter Nesser, “Assessing the Islamic State’s Commitment to Attacking the West,” Perspectives on Terrorism 9, no. 4 (2015): 14–30, Assessing the Islamic State’s Commitment to Attacking the West – University of Mary Washington.