Can Turkey Stabilise Syria?

Out of the ashes of Bashar al-Assad’s regime, Turkey’s ruling Justice and Development Party has emerged triumphant, having indirectly supported a rebel offensive led by Hay’at Tahrir al-Sham (HTS) that toppled the Syrian regime. But a seismic shift of this scale – the removal of the decades-old House of Assad – may inadvertently set in motion a series of events over which Ankara cannot exert a monopoly or even control. Setting the parameters for Turkey’s stabilisation strategy will be critical for Syria and the dynamics emerging across a rapidly shifting region. 

Syria’s fluid security situation (parts of the country are still out of HTS’s reach), uncertainty about the future of US policy on the Kurdish-led Syrian Democratic Forces (SDF) in northeastern Syria under President-elect Donald Trump, and signs of a resurgence of so-called Islamic State mean that Turkey faces several challenges. 

Turkey’s current approach favours centralisation and consolidation of Syrian state institutions while supporting HTS as the caretaker government, as well as facilitating its diplomatic outreach and efforts to attract foreign investment, humanitarian aid and economic links. But a month since Assad’s ouster, there are clear signs of the extent of the risks that lie ahead. In the coming period, if HTS is seen to delay the convening of the planned National Dialogue Conference to include actors from across Syria’s diverse political, ethnic, religious and sectarian spectrum, prolongs the holding of national elections, or is seen to implement a Salafi-oriented legal system without a mandate, then it will lose the goodwill of Syrians and international actors alike. 

Moreover, in a nightmare scenario where HTS fails to stem violence against Alawites or Christians and sectarian violence grows, it will clearly have failed as a governing actor. Turkey, seen as a major supporter of the jihadi turned party leader Ahmed al-Sharaa, will lose its credibility and the opportunity to capitalise on the historic geostrategic shifts underway in the region, with a weakened Iran and Russia. Instead, Ankara must balance a proactive foreign policy in Syria with a cooperative, multilateral approach to engage with foreign actors like the US and regional allies to support an inclusive Syrian-led transition. Otherwise, Ankara faces the risk of overreaching in Syria.

Security Sector Policy

In interviews with the authors, Turkish officials described the overthrow of Assad as a ‘paradigm shift’ with wide-ranging and fast-evolving consequences, signalling the centrality that Syria holds from Turkey’s national security perspective. But they insist that Turkey is not vying to replace the dominance over Syria previously exercised by Iran, which weaponised a destabilising agenda for decades. Turkey views Syria’s political stability and security as being interlinked. Across the Turkish border, thousands of fighters aligned with various armed groups still operate within Syria. Should HTS falter in its bid to unify these disparate factions – once united against a common adversary – under a centralised defence structure, Ankara could face mounting instability along its 900-km frontier. 

The Turkish defence minister, Yasar Guler, has said that Turkey is prepared to provide military training if the Syrian administration requests it. Turkey has conducted several major counterterrorism operations across its southern border since 2016 and is estimated to maintain around 10,000 troops in towns and military outposts including Afrin, Azez and Jarablus in northwestern Syria and Ras al Ain and Tel Abyad in the northeast. The real figure is likely to be much higher. 

According to reports, Turkey is ready to send military advisors to support the training of the new Syrian army at military academies in Aleppo and Damascus. On 2 January, the Turkish Ministry of Defence stated that talks are underway to further military cooperation with the transitional administration. Turkey’s assistance could have a positive impact on army unification and professionalisation. But there are challenges to this process stemming from internal and external dynamics.

Soon after the collapse of regime forces, al-Sharaa called for respect for the rule of law, instructed against seeking vigilante-style justice against former army officials, extended amnesties for conscripts, and set up a disarmament registration system in many parts of the country. On 24 December, the chiefs of some of Syria’s ‘revolutionary factions’ agreed to be dissolved and merge under the country’s Defence Ministry. While the bloodless capture of Damascus bodes well for the prospect of a successful transition, any consensus among former rival factions may prove fragile as actors tussle for financial resources, rank and political status. For example, two of the largest Druze armed groups in Sweida announced they would join a new national army as long as their rights were guaranteed and the army was not run according to factional or sectarian rules. 

The HTS-led General Command’s decision to promote certain militant group leaders, including Khalid Khattab, head of the hardline militia Ansar al-Tawhid, to senior army posts alongside foreign fighters and HTS commanders illustrates the competing pressures that al-Sharaa and his allies face in integrating armed groups into a unified structure. The vast majority of the 49 men promoted are HTS field commanders and members of jihadi groups who lack formal military training and credentials. The decision to award titles to foreign fighters (including Uighurs, a Tajik national, a Jordanian, a Turk, an Egyptian and an Albanian) has drawn strident criticism. But al-Sharaa’s immediate task is to unify a patchwork of disparate armed groups, and these steps may be read as alliance-building and seeking to deter them from splintering or acting unilaterally against his nascent authority. 

Over the past decade, Turkey has ramped up its security-related cooperation with several African states, including military training and the opening of training facilities, such as in Libya and Somalia. Such engagement offers a blueprint for how Ankara plans to approach the Syrian case. But state-to-state military training presents a different set of challenges to militia demobilisation and integration, which can be constrained by intra-group rivalries motivated by identity-driven or profit-seeking behaviour. Where some armed factions have a vested interest in retaining control over smaller units or wish to ‘own’ command over tribal or sectarian loyalties that sit outside of formal structures, the process can be slow and arduous. Without an appropriate balance of incentives-to-payoffs, Salafi-jihadi groups that see themselves losing profitable economic and political influence could undermine centralisation and reform strategies. 

The enormity of the task should not be underestimated. Deteriorating domestic security, including sectarian or intra-militia violence, will mean that the task of security provision falls on loosely organised rebel groups with varying stockpiles, training and levels of cohesion. A further complication is that, according to Turkish sources, there may be approximately   8,000 foreign fighters in Syria, including Russians, Dagestanis, Chechens, Uzbeks and Tajiks (excluding Islamic State). It remains unclear what will happen to pro-regime Lebanese, Iranian and Iraqi fighters who were naturalised under Assad. Implementing a policy that addresses these risks will require planning, but with the security landscape fractured and not enough personnel in HTS’s ranks to secure the whole country, this will be a complex, incremental process.

Moreover, the scale of the latent threat posed by loyalists from the former army officers' corps and pro-regime paramilitary militia is unclear. According to our sources, over 32,000 former army personnel are believed to have handed in their weapons since HTS set up registration and reconciliation centres. But hundreds of officers and thousands of loyalists are believed to remain underground, and some are in hiding in Libya, the UAE and Iraq. Despite this, it is unlikely that the old nationalist guard could leverage a coordinated threat in the short term; instead, some may seek eventual reintegration, while others could mobilise to exploit vulnerabilities within the new security apparatus. 

Given these high-risk and volatile dynamics, Turkey should avoid taking on unilateral responsibility and instead deploy advice and training to build the capacity of HTS-led Syrian forces to meet challenges directly. A number of recent reports connecting some fighters with HTS links to acts of extrajudicial or revenge killings against former Assad loyalists, as well as allegations of violence against minority groups, have undermined confidence in HTS. While many reports are false or unverified, it will be important for al-Sharaa to demonstrate effective leadership as well as tactical and operational command over the HTS rank and file. In order for Turkey’s security sector reform role to be effective, there is still much heavy lifting to be done to clarify the parameters and means of implementation.

Who Will Confront a Resurging Islamic State Threat? 

An uptick in Islamic State mobilisation in the past year and concurrent propaganda techniques indicate that the group seeks to exploit the fall of the Assad regime and the regional shifts triggered by Israel’s war against Hamas in Gaza. There are genuine concerns that Islamic State cells will try to exploit a political crisis and security vacuum at the centre of the Syrian state to expand its areas of operation. Last year, US Central Command estimated the number of Islamic State fighters in Syria and Iraq to be about 2,500. Around 9,000 Islamic State detainees remain in over 20 detention facilities in northeastern and eastern Syria, guarded by the US-backed SDF, with a further 40,000 family members of Islamic State fighters held in camps. 

According to sources familiar with Turkey’s military engagement in Syria, Turkey views Islamic State through two lenses simultaneously. One is the threat of the ‘ghost of Daesh’, which is seen as a way for the SDF to justify continued military training, arms and funding provided by the US and to maintain a territorial foothold. The second lens recognises and is prepared to counter the growing terrorist threat posed by Islamic State activity in Syria amid a risk of a security vacuum, and positions Turkey as playing a key counterterrorism role. 

On 22 December, in a joint press briefing with al-Sharaa, Turkish Foreign Minister Hakan Fidan said the Syrian government was prepared to take control of Islamic State prisoners and the camps. This has raised some concerns among Western policymakers. al-Sharaa (then using his nom de guerre, Abu Muhammad al-Jolani) fought in the post-2003 Iraqi insurgency as a member of the Islamic State of Iraq. Some of the fighters under the HTS tent, particularly foreign fighters, adhere to more radical Salafi or sectarian jihadi views, raising questions about their commitment to countering Islamic State extremism. However, HTS has fought against Islamic State for a number of years, and since HTS parted with al-Qa’ida in 2016, it has taken steps to increase its visibility as a legitimacy-seeking group that has denounced transnational jihad. The nature of warfare evolved from insurgent fighting in 2014 to a type of counterterrorism approach against Islamic State cells in HTS-controlled territory in northwestern Idlib from 2017, a process that accelerated after the March 2020 ceasefire between Russia and Turkey. 

An agreement that sees an HTS-centred, unified Syrian armed force assume greater responsibility over Islamic State detention centres may dampen some of the tension between the US and Turkey, two NATO allies. Additionally, once HTS is able to establish a fair and functioning judiciary, the Syrian legal system must be able to prosecute former Islamic State fighters according to national legislation. Admittedly, this will be a lengthy process, but the mission to degrade and defeat Islamic State can be more effective with a well-resourced and trained national Syrian partner. 

The Dispute over the SDF in Northeastern Syria

US support for the SDF, which is led primarily by the Kurdish People's Defense Units (YPG), a group that Ankara sees as an extension of the Kurdistan Workers’ Party (PKK) – an organisation designated as terrorist by the US, UK and EU – is predicated on the SDF’s role in combatting Islamic State. Since the fall of the regime, northern Syria has witnessed clashes between the Syrian National Army (SNA) – a coalition of Turkish-backed militias – and the SDF as competition has intensified.

There is a significant divergence in how Washington and Ankara view the SDF, and lasting stability in Syria is not a viable prospect unless questions around the status of the Kurdish militia are resolved.

Turkey’s recent efforts to tentatively relaunch a process to resolve the country’s protracted conflict with the PKK, which has waged war on Turkey for 40 years, are motivated by the dynamic situation in Syria, and the possibility that the SDF may consolidate territorial control with Washington’s sponsorship ahead of a likely US troop withdrawal under Trump. Turkey is likely making long-term assessments about shifting dynamics in the Middle East that could favour Kurdish secessionist claims, such as recent overtures by some Israeli government officials in support of Kurdish autonomy in Syria against the backdrop of a severe breakdown in Turkey–Israel relations. Iran poses a dual threat, with the prospect of either a weakening of the regime in Tehran – which could revive Kurdish ambitions inside Iran – or alternatively, Iranian stoking of YPG–PKK armed violence to undermine Turkish interests in Syria and Iraq.

The future of the SDF, including its political status and militia demobilisation, will strain US–Turkey talks on Syria as Trump returns to the White House. Although Trump has previously stated that he wants US troops to withdraw, the fluid security environment, coupled with the deadly Islamic State-linked terror attack in New Orleans on 1 January, suggests that this will be met with resistance by the Pentagon, which recently announced that about 2,000 US special forces are currently stationed in Syria, up from the 900 previously disclosed. 

Despite an initial meeting between al-Sharaa and the SDF leadership in late December, the SDF has not formally agreed to terms to integrate into a national army. While other groups – including the Turkmen Brigades and some elements of the Turkey-backed SNA – have expressed reservations, it appears that all of them have agreed in principle to the process of centralisation. Recent weeks have seen sporadic Arab tribes in parts of Raqqa, Deir ez-Zour and Hasakah staging protests against YPG-led forces, adding strain to the already embattled Kurdish-run administration in Arab-majority areas. These pressures underscore the growing need for a political settlement to address the fragmented control of the country.

The merger of Syria’s expansive patchwork of militia into a unified army will contribute to Syria’s counterterrorism role against Islamic State. There are three reasons for this. First, a state-to-state security cooperation framework is better suited to neutralising the growing threat posed by Islamic State, while strengthening Syrian central military capabilities and increasing security at the national level. Second, de-radicalisation of former Islamic State fighters at the scale required – thousands of fighters and a secondary network of potential recruits – can be implemented through the deployment of state-level resources and capability. Third, relying on the SDF as the main line of defence against the resurgence of Islamic State may prove insufficient as the group pivots in the coming months to matters concerning its internal organisation, status and integration within the emerging Syrian state apparatus, both politically and militarily.

Strong mechanisms for training and coordination to oversee the handover of Islamic State detainees to a Syrian central authority should be agreed between the US and Turkey and implemented directly – with oversight if required – by the newly constituted national Syrian army. In the coming months, it will become clearer what role Syrian Kurds may play in this arrangement.

It is clear that Washington and Ankara share strategic interests in Syria. The rapid dismantling of Iranian influence over Syria is a win that both sides will seek to maintain. The US and Turkey stand to benefit from a stable Syrian state with functioning institutions, and Ankara’s influence over Syria’s de facto rulers could act as a moderating force as HTS shifts from an armed jihadi movement to a political party. 

Charting the Path Ahead

Post-authoritarian transitions are inherently fragile. In the absence of a transitional process that has broad-based support and representation from across Syria’s constituent groups, the country risks slipping into renewed violence, a neo-authoritarian style of rule, or state failure. The track record of post-Arab Spring democratic transitions in the Middle East and North Africa is not encouraging. Neighbouring states can help mitigate these risks by playing a constructive role and supporting authorised national-level actors and processes.

Despite the fall of Assad, it is too soon to describe the country as being in a post-conflict phase. Ankara must strike a balancing act in its approach to Syria. If it is seen to be meddling in domestic affairs or positioning for an indefinite military presence, this may have negative consequences for its stabilising role. Instead, Turkey can use this opportunity to help regional states, such as Qatar and Saudi Arabia, to become meaningfully involved to alleviate the pressure on Ankara while encouraging burden-sharing in the rehabilitation of Syria’s economy and infrastructure. 

© RUSI, 2025

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