Turkish-Iranian relations have a constant characteristic defined in the last century and generally, the nature of these relations are extremely predictable. Various determinants, such as an absence of border issues, full awareness of each other’s reflexes due to a shared centuries-old empire mentality, and close collaboration on bureaucratic security procedures until the Islamic Revolution, have inhibited any radical changes to occur in bilateral relations (iramcenter.org/).
Historically, Turkey and Iran have been mirror images of one another, rarely seeing eye-to-eye, but unable to part ways due to their geographic proximity. Both countries opposed the American invasion and occupation, which they feared could restrict their room to maneuver in their historical sphere of influence. Second, they were suspicious that America would support Kurdish nationalism in northern Iraq and were wary of the invasion’s broader impact on the Sunni-Shia balance in the region.
Yet despite its initial opposition to the invasion, Ankara stood closer to Washington in pursuit of Turkey’s regional goals, while Iran maintained close bonds with the Shia majority and pro-Iranian Shia militias were increasingly targeting U.S. troops in Iraq (americanprogress.org/).
Turkey and Iran continued to compete from Iraq to Syria and Lebanon and from the Gulf to Afghanistan. The Syrian conflict and Turkey and Iran’s divergent policy choices became a bone of contention for the two rival regional powers.
While Turkey framed the growing conflict as a humanitarian issue and an opportunity to enhance its regional clout, Iran saw the rebellion against President Bashar al-Assad’s regime as a critical threat. This was because the Iranian establishment considered Syria to be a firewall that would block the disruptive impact of the Arab Spring from toppling regimes friendly to Iran or from reaching its own borders.
Turkey worked through proxies but refrained from directly embroiling itself militarily (americanprogress.org/). Turkish border cities became a chief logistical hub for foreign fighters seeking to enter Syria and Iraq to join ISIS and other rebel groups. By August 2015, Turkey did eventually tighten up security on its borders (english.alarabiya.net/).
Iran, by contrast, employed more direct proxies such as Hezbollah and later deployed its own paramilitary assets to prevent the fall of Damascus. Iran did not hesitate to use the sectarian card in the conflict, employing Shia militias in Syria and Iraq against what it called the forces of extremism, which included not only Al Qaeda and its offshoots—including the Islamic State—but also almost all Sunni rebel groups fighting the Assad regime in Syria.
While Iran aggressively pursued its goals—emphasizing the fight against what it regarded as Sunni extremism—the marginalization of Sunni interests drove Turkey and Saudi Arabia to set aside their ideological differences to stand together against Iranian expansionism. The interaction between the sectarianism stoked by both the Sunni and Shia elements involved in the Syrian civil war and escalating Iranian-Arab and Turkish-Kurdish confrontations is shaking the foundations of the regional order and undermining security and stability. (americanprogress.org/issues/). This tension has also extended into the Iraq conflict.
In Iraq, Turkey claims that it has a historical responsibility to protect the country's Sunni and Turkmen minorities from Iran-backed Shia militias who are in the region to fight ISIL.
Iran, on the other hand, alongside with Iraq's government, views Turkey's involvement in the conflict and military presence in the country as an incursion. Turkey 's President Recep Tayyip Erdogan accused Iran of trying to split Iraq and Syria by resorting to Persian nationalism, while Mevlut Cavusoglu, Turkey's foreign minister, criticized what he called Iran's sectarian policy aimed at undermining Bahrain and Saudi Arabia. The fear was that Iran was trying to create two Shia states in Syria and Iraq As ISIL is steadily losing large swaths of territory in both Iraq and Syria, a significant power vacuum is forming along Turkey's southeastern border, causing Iran and Turkey to clash over who is going to replace the dominant force in the area. The tensions between the two powers were escalating greatly as late as early 2017 (aljazeera.com/). Then in late 2017 circumstances changed the dynamic.
The lack of Arab presence and its inability to formulate new parameters for national and regional security have allowed Turkey and Iran to balance their regional roles within the Arab world.
Turkey and Iran have given the military dimension an important role in shaping their regional role. Turkey used pre-emptive military intervention in its movements in the Arab region after adopting a defensive military approach based on protecting the borders. Turkey is also using its economic growth by branding itself as a country with Islamic economy to serve the Arab and Muslim countries.
The Syrian crisis showed the overlap of issues in the region and that no issue can be resolved without resolving the other and that the regional players should be involved with superpowers to bring solutions to these questions politically. Thus, the Syrian dilemma is looking more and more difficult to solve and radical Islamists have become the common enemy of all (english.alarabiya.net/).
The two countries’ joint stance on the illegitimate referendum in Kurdistan, their joint action with Russia through the Astana Process to minimize the conflicts in Syria; furthermore, their common position on nullifying the conspiracy against the Qatar administration illustrate that the tensions experienced for the past five years between Iran and Turkey have ended and the two countries have begun to increase their alliance (iramcenter.org/).
For the first time in history, military visits were made between Iran and Turkey at the level of Chief of General Staff. This allowed Turkey to organize a military operation on a larger and more strategic area within Syria with relatively low risk, and by mid-October, Turkish troops were situated in various regions of Idlib (iramcenter.org/).
In recent years, relations between the two countries have been developing in all fields of mutual interest and is continuing along this path to serve both nations' interests. President Hassan Rouhani said that the Islamic Republic of Iran and Turkey enjoy ample historical and cultural commonalities and further deepening of bilateral, regional and international relations between the two countries would be beneficial for peace and stability in the region and the world (iran-daily.com/).
It is not just the military and economic considerations that are driving the sudden change in attitudes between the two countries. Their roles in the Syrian/Iraq conflict and other past political stances have left both sides in compromising positions.
Iran is surrounded by Sunni-majority countries and can only hope to realize its domestic and regional goals in cooperation—or at least coexistence—with the rest of the neighborhood. Gulf monarchies are apprehensive about Iranian encroachment in Iraq, Syria, Yemen, and beyond. In response, they are relying on a military buildup and the power of religious orthodoxy to help deter and roll back Iranian intrusion into what they regard as a rightfully Sunni Arab sphere of influence. For Turkey, its official discourse against sectarianism does not change the fact that it is now seen as a pro-Sunni power and, in general, has alienated Shia actors in the region.
This does not bode well for Turkey’s broader aims of regional integration nor its internal dynamics given its large Alawite and Kurdish populations, who feel threatened by the Islamic State and remain suspicious of the growing Turkish affinity with Sunni causes (americanprogress.org/).
Ultimately the real driving force behind this is the threat of Kurdish nationalism and the rise of autonomous Kurdish states in the region. In Turkey, the PKK (Kurdish Workers Party) has resumed its terror campaign against the Turkish state. Iran will be watching these developments closely, nervous about its own Kurdish minority and well aware that the PKK seeks to overturn the existing state order in both Turkey and Iran.
Indeed, the PKK and its offshoots’ continued threat to Iran’s national unity was again demonstrated by the recent clashes in northwestern Iran. Kurdish separatism is a real possibility in both Syria and Iraq and is a more distant if just as divisive threat in Turkey and Iran. The Kurdistan Regional Government in Iraq enjoys strong U.S. support and continues to flirt with the idea of independence. Syrian Kurdish fighters are building de facto autonomy on the ground and enjoy military support from both the United States and Russia, though this is likely to dry up once the Islamic State is defeated (americanprogress.org/).
The decision by both nations to change so abruptly from the last five years of hostility and competition towards working together is rooted in several mutual concerns and interests. That said it is unlikely this alliance is going to be a short-lived relationship. The possible rise of autonomous Kurdish regions especially in a centralized location like Northern Syria and Iraq offers a serious security concern that is igniting another round of destabilizing hostilities in the region. Inevitably this fact alone is likely going to bring Iran and Turkey more closely together as their security interests further align.
It is unlikely that Turkey will simply sever ties with the U.S. over the Kurdish issue. Turkey will continue to try and walk a line maintaining relations with the U.S. as a powerful ally while cultivating stronger ties with Iran, with whom they share grave security concerns.
It is too early to predict what this new relationship means in the interim. This could serve to strengthen Iran’s position; who in the aftermath of the ISIS conflict is left with significant control within both the Syrian and Iraqi governments and will now have means to marginalize the threat of one of their biggest rivals in the region. This could also be an avenue for resolution with the west whereby Iran’s economic interest will force it to pursue a more negotiable position with its previous enemies.