The second reason for this shift is the fact that unilateral strategic choices have not succeeded on the ground. Neither Turkey’s choice to seek the toppling of Syrian President Bashar al-Assad nor Iran’s policy of restoring stability in a unified Syria has materialized. Yet, Iran’s strategic investment in Syria has proved successful in stopping what Tehran has viewed as a plot against its allies.
Meanwhile, Turkey’s investment in arming and supporting the Syrian opposition has not only failed to oust Assad, but also caused security and strategic challenges for itself.
After finding itself up against the Islamic State, Turkey’s security has been jeopardized, as seen in the unprecedented bombings on its soil. Ankara’s policies have also led to the empowerment of Syrian Kurds, whom Turkey depicts as terrorists due to their historical affiliation with the Kurdistan Workers Party. Turkey’s strategic choices on the Syrian crisis have opened a Pandora’s box whose contents are spilling over into its own territory. Partnering up with Saudi Arabia and Qatar in support of the Syrian opposition has failed to change this strategic impasse for Ankara.
The third reason for the change in Turkey’s tone toward Iran stems from the shifting dynamics of the Syrian crisis after the Russian military intervention, and especially following Turkey’s downing of a Russian fighter jet in November. It is obvious now that the latter was a miscalculation. No matter what Ankara’s reasons for the shooting down of the jet were, it led to Russia’s deployment of the advanced S-400 air defense system on Syrian territory, thereby limiting Turkey’s scope for maneuvering. It also made Russia the second international power, after the United States, to back the Syrian Kurds. This has hit a nerve in Ankara — yet Turkey has not been able to do anything about it.