For months, Turkey has been threatening to send troops across its southern border into predominantly Kurdish northeastern Syria. It would be Turkey's third military offensive in northern Syria, following interventions in 2016 and 2018. The United States, meanwhile, has warned Turkey that any hostile action will be punished.

Yet last week, both sides met in Ankara to flesh out an agreement creating a safe zone along the Turkish-Syrian border. The area will be controlled by Turkey. To facilitate the process, the US and Turkey will establish a joint operations center in the region. According to Turkish Defense Minister Hulusi Akar, the command post will be operational within the next few days.

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Details about the planned "peace corridor" so far remain vague. Above all, Turkish authorities want to create a buffer zone east of the Euphrates River in order to force fighters from the Kurdish Peoples Protection Units (YPG) from the region.

The Turkish Foreign Ministry says it is currently "mopping up" along the Turkish-Syrian border. Turkey's government considers the YPG, which controls larges swatches of northern Syria, an offshoot of the Kurdistan Workers' Party (PKK). Ankara has classified the PKK as a terrorist organization and views it as a threat to its national security.

Friends or foes?

Washington, on the other hand, considers the YPG one of its key allies in the fight against the Islamic State group. The US has armed, trained and fought alongside YPG soldiers in recent years. The alliance has been successful in largely defeating Islamic State fighters in northern Syria. Washington now fears that if Turkey expells YPG forces from the region, the ensuring power vacuum could be filled by insurgent militant groups.

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In addition, there seems to be disagreement over how wide the proposed "peace corridor" should be. Turkey's defense minister on Monday said the buffer zone would be between 30 and 40 kilometers (19-25 miles) wide, whereas the US had proposed something half this size.

Kurds excluded from talks

And the fate of northern Syria's Kurds remains unknown, too. Aldar Khalil, a senior Kurdish official in Syria, said "the details of the [US-Turkish] agreement are completely unclear." The Kurds had wanted to be included in talks, he explained, "but Turkey was not interested in trilateral dialogue."

"A solution reached by Syrians to take matters into their own hands would have been the right approach," Khalil said, adding he doubts doubts Turkey is really seeking security and peace. Instead, Khalil believes, "Turkey is trying to expand its borders and to instrumentalize the Syrian war to further its own agenda."

The Kurds and Syrian government have expressed concern that Turkey may plan to expel the local Kurdish population from norther Syria through another military offensive. In 2018, Turkish forces assaulted the city of Afrin, in northern Syria.

"After the military operation there were abductions, extortions, there was looting, and Afrin-based Kurds were driven from their homes and replaced by the families of jihadis," said Muhammed Bakir of the Rojava Center for Strategic Studies, adding he was concerned that this expulsion of Kurds could endanger the long-term stability and security of the region.     

Returning Syrian refugees

The buffer zone agreed between Washington and Ankara is officially designed to allow Syrian refugees to return to the country's north. Indeed, a statement released by both parties says the "peace corridor is intended to allow displaced refugees to return to their homes." No country in the world has taken in as many Syrian refugees as neighboring Turkey. But since the onset of Turkey's economic crisis last summer, which has put growing pressure on the domestic labor market, resentment is growing against the 3.6 million Syrians refugees in the country.

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Washington, meanwhile, is keen to avoid Syria descending into chaos and groups such as Islamic State regaining influence after it withdraws its troops. In January, US President Donald Trump warned his government would "devastate Turkey economically if they hit [the] Kurds" after the US starts its "long overdue" pullout from Syria.