Attention is focused on Turkey's Operation Olive Branch in Afrin in northwestern Syria, but an equally important Turkish military effort is underway in neighboring Idlib province. Taking advantage of Russia's increasing willingness to freeze the Syrian conflict between the rebels and the Syrian government, and determined to prevent further gains by loyalist forces close to its borders, Turkey has ramped up its effort to station blocking forces between rebel and loyalist forces in Idlib.
This undertaking not only draws Turkey deeper into the Syrian civil war, but it also further strains its relationship with Iran. Iran and Turkey are longtime rivals, with the Levant, Iraq and much of the wider Middle East historically an area of intense competition between the two regional powers. Ankara's further reach into Syria will only intensify the proxy conflict between Turkey and Iran in Syria. Nevertheless, given the importance of their economic relationship, their shared opposition to Kurdish separatism and Iran's growing concern with a wider U.S.-backed front against it, the proxy conflict between Turkey and Iran is unlikely to escalate to an entirely adversarial relationship. Instead, Iran and Turkey will seek to compartmentalize their conflict into areas of competition and collaboration in the wider region.
De-Escalation Zones and Retaliation
Over the past couple of weeks, a number of Turkish military convoys have made their way through Idlib province toward the front lines between rebel and loyalist forces. In explaining these deployments, Ankara pointed to the "de-escalation" framework agreed upon with Russia during the Astana talks that sought to establish and monitor a ceasefire zone in northwestern Syria. Through the sochi peace process, Russia had sought to secure a political solution to the conflict that is favorable to its interests. The failure of the Sochi peace process, however, has galvanized Russia toward reinforcing its secondary strategy with Turkey, which is to freeze the conflict through de-escalation zones such as the one in Idlib. Given that Syrian government forces and their allies are on the verge of driving deep into Idlib, Turkey increasingly has been willing to work with Russia on this strategy to impede any further loyalist gains toward its border.
Though Turkey and Russia increasingly see eye to eye on the Idlib de-escalation zone (although numerous differences remain between the two on the conflict), the Syrian government's other key ally, Iran, is less willing to entertain a greater Turkish involvement in the country and conflict. The Turkish military convoys moving through Idlib have come under attack a number of times. A Turkish soldier was killed and five others wounded in the most recent significant attack on Feb. 6, which seems to have been initiated by loyalist forces operating under the direction of Iranian Islamic Revolutionary Guard Corps (IRGC) officers in the Hader area south of Aleppo city. The attack marks the first time a Turkish soldier was killed in Syria by Iranian-directed forces, and is likely to be only a preview of what is to come.
Iran has invested large amounts of resources into bolstering the Syrian government's effort to defeat the rebellion, and is far more willing to pursue a total military victory in Syria than Russia. Further, Iran perceives Turkey as a major regional competitor, and is unwilling to stand by as Ankara increases its influence in Syria. Even before the latest attacks on the Turkish convoy, this was evident in the often pragmatic approach that Iran and Damascus have taken toward the Kurdish People's Protection Units (YPG).
Beyond Syria, increased Iranian anger at Turkish encroachment could drive Iran to leverage its considerable influence in Baghdad to push back against Turkish operations in Iraq.
Even as the loyalists have battled with the YPG at times — most recently on Feb. 8 in Deir el-Zour — Syrian government forces and Iranian-backed militias have not hesitated to support the YPG when the Kurdish militia fought Turkish forces and their allies. The Afrin operation offers a recent visible example, with the Syrian government allowing YPG fighters to move through its territory to confront Turkish forces. Furthermore, there is considerable evidence that Damascus and Tehran are supplying the YPG in Afrin with weaponry that ranges from Iranian-made artillery rockets to stocks of anti-tank guided missiles.
Beyond Syria, increased Iranian anger at Turkish encroachment could drive Tehran to leverage its influence in Baghdad to push back against Turkish operations in Iraq. Turkey recently has highlighted a desire to pursue a combined Turkish-Iraqi offensive against groups affiliated with the Kurdistan Workers' Party (PKK) in the Sinjar region of Iraq. Although Iraq and Iran enjoy a close relationship, Iraq's relatively weak geopolitical position means it must maintain a pragmatic working relationship with Turkey as well, and Ankara and Baghdad have found common ground in the wake of the Kurdish independence referendum in late 2017. Iran is motivated to try to prevent any Ankara-Baghdad relationship that could threaten Ankara-Tehran ties. Not only could Iran move to position its allied Iraqi militia proxies to challenge any Turkish drive southward, it also could pressure the Iraqi government to not join the Turks in such an endeavor.
Where Resistance Meets Accommodation
Even as Iran seeks to punish Turkey for its greater direct involvement in Syria, there are a number of reasons why Tehran may seek to largely limit its retaliation to the battle space in Syria and, to a much more limited extent, Iraq. And those reasons could cause Iran to follow a more pragmatic approach toward Turkish ambitions that compartmentalizes their mutual relationship into areas of dispute and areas of cooperation.
First, Iran and Turkey have a growing economic relationship, with more than $8 billion in trade volume. In addition, Turkey imports about 20 percent of its crude and condensate supplies from Iran, and about 16 percent of its natural gas needs. Iran in particular will be keen to not jeopardize its economy at a time of increased economically motivated protests at home. Furthermore, Iran and Turkey share some common goals in pushing back against Kurdish separatism. So, while Turkey and Iran are willing to work with various Kurdish groups across the region, both will be careful keep their efforts to leverage the Kurds against each other from undermining their wider goal of preventing an independent Kurdish state. There also have been increased collaboration efforts between Ankara and Tehran recently to enhance their security on their mutual borders.
Perhaps most importantly, Iran is aware of an anti-Iranian front mobilizing against it in the region. This front is manifest in a growing alignment between Israel and Saudi Arabia backed by a more aggressively anti-Iranian administration in the United States. Tehran is already attempting to salvage the Iran nuclear agreement, and there are signs that Iran already has taken measures to draw down some of its provocative actions — for instance, by stopping IRGC harassment maneuvers in the Persian Gulf against U.S. warships since August 2017. For Tehran, an aggressive strategy against Turkey when it is facing a pushback across the region is unlikely to be a desirable path forward. It is little surprise then that Turkey and Iran are increasing their efforts to manage their relationship amid stress in Syria, with Turkish Foreign Minister Mevlut Cavusoglu visiting Tehran for talks with his Iranian counterpart, Javad Zarif, on Feb. 7 and reports published on Feb. 8 that a meeting between Turkish President Recep Tayyip Erdogan and Iranian President Hassan Rouhani may be in the offing.
Turkey's increasing involvement in Syria will drive Iran to retaliate, but a number of underlying systemic considerations will limit the intensifying proxy war between these two regional powers to the battlefield itself, particularly in Syria and Iraq. In much the same way that Turkey and Russia have been able to improve their ties even as they find themselves on opposing sides of the Syrian conflict, Turkey and Iran have cause to cooperate in some areas while continuing to compet in others.