In mid-2016, Ankara found itself reconsidering the situation in Syria for several reasons and changed its priorities. Russia intervened on the side of Bashar Assad following Iran. The regime forces, with air support from Russia and reinforced by Iran-backed militias on the ground, recaptured territories lost to opposition groups. The U.S. administration that had loudly called on Assad to step down in the first place had changed its Syria policy in 2013, and chose to do nothing while hundreds of thousands were killed and millions were displaced. The refugee flow scared European countries to death, and their priority was to secure a deal with Turkey to block the influx. Turkey was abandoned by its U.S.-led Western allies.
Meanwhile, the Daesh terrorist organization defeated opposition fighters in the north and took territory on the Turkish-Syrian border, while another terrorist organization, the outlawed PKK's Syrian affiliate Democratic Union Party's (PYD) People Protection Units (YPG), got huge support from the U.S.-led coalition to counter Daesh after the Assad regime gave control of the territory to the PYD in northern Syria in a deal. Turkey's border with Syria was then totally controlled by two terrorist groups – Daesh and the YPG – which fought against each other to gain more land. Washington has kept saying that the reason the U.S. supports the YPG is only to fight against Daesh, but both Daesh and the PKK conducted dozens of terrorist attacks in Turkey, killing more than 400 in 2015 and 2016. Most of the weapons the PKK used in the attacks in Turkey were given to the YPG for the fight against Daesh in Syria by the countries in the U.S.-led coalition.
The PKK and Daesh's attempts to carry their fight into Turkey started to threaten the country's stability more every day, and Turkey's NATO allies were reluctant to see the situation clearly. Intriguingly, the PKK has been listed as a terrorist network in the U.S. and the EU as well as Turkey. It has been very well known that the PYD was founded by the PKK's umbrella organization, the Kurdistan Communities Union (KCK), under the directions of imprisoned PKK leader Abdullah Öcalan. Turkish authorities shared evidence that the weapons given to the YPG by the U.S. were used by the PKK in attacks in Turkey many times, but that has been ignored. Still, Turkey has been determined to eliminate terrorist groups on its borders, be it Daesh or the YPG.
Ankara was running out of patience, and how Washington acted during and after the July 15, 2016 coup attempt staged by the Gülenist Terror Group (FETÖ) was the last straw. The failed coup's aim was not only to overthrow the government and assassinate President Recep Tayyip Erdoğan, but to change Turkish affairs, including its Syria policy, by replacing the elected government with a Gülenist regime. On Aug. 24, 2016, only 40 days after the attempted coup, the Turkish Armed Forces (TSK) launched Operation Euphrates Shield in Syria to cleanse Daesh elements from its borders. The Turkish military was thought to be weak because of the failed coup. However, it showed great success in northern Syria very quickly, although it was cleaning the Gülenists from among its soldiers at the same time.
Operation Euphrates Shield officially ended in March 2017, but Turkey never stopped helping to rebuild the liberated Syrian towns or delivering assistance, services and humanitarian aid to the people who finally found some peace in Syria.
In addition, Erdoğan and Russian President Vladimir Putin agreed on a proposal for a general cease-fire in Syria and pushed for talks without the U.S. or U.N. Both leaders suggested Astana, Kazakhstan as a new venue for carrying on Syria peace talks. The cease-fire drastically reduced violence in Syria, and the Astana talks, with Iran joining Russia and Turkey as a third guarantor, marked a distinct change from the diplomatic failures of the talks led by the U.N. in Geneva.
Washington has been uncomfortable with Ankara's closeness with Moscow and Tehran since then, but to be honest, it has not left Ankara any other choice. There are two terrorist organizations seen as existential threats by Turkey – the PKK and the FETÖ – and yet, the U.S., a long-term NATO ally, has been supporting the PKK's Syrian affiliate as an ally on the ground while letting Fetullah Gülen, the leader of FETÖ, and top Gülenists continue their activities in the U.S. If that is not a betrayal, then what is?
The ties between the U.S. and Turkey were severed in the last months of President Barack Obama's final term, but Ankara chose to wait and see how the next U.S. president would approach Syria, and if the new administration would understand Ankara's concerns. The administration of President Donald Trump continued to support the YPG, but still, Ankara, giving a last chance, waited until the defeat of Daesh in Raqqa, the so-called capital of the notorious terrorist group. In October, the YPG raised its flags and the posters of Öcalan in the city center of Raqqa. In November, Trump said in a telephone call with Erdoğan that the U.S. was going to stop arming the YPG. That was another broken promise given to Turkey.
Obviously, the U.S.'s last decision to form a 30,000-strong border security force from the YPG-dominated Syrian Democratic Forces (SDF) was something that Ankara would not tolerate under any circumstances. Angry statements from Turkish officials quickly turned into a military operation, Operation Olive Branch, launched by the TSK into Afrin, a Syrian town under the control of the PYD. Although the PYD in Afrin is not supported by the U.S., according to official statements coming from Ankara, Turkey's next target will be Manbij, another Syrian town, which the U.S. promised to withdraw YPG forces from long ago, but has not done so. Now, U.S. Secretary of State Rex Tillerson says the issue has been misportrayed, denying the U.S. intention to form a border security force. Trump has asked to speak to Erdoğan by phone. One really wonders if a new promise that will not be kept is about to be given, or will Washington finally understand that it has to take some concrete steps to gain Turkey's trust?