Two NATO allies, Washington and Ankara, woke up to a furious tweet from US President Donald Trump. In it, he threatened Turkey with economic sanctions again, warning it against entering northern Syria to fight the YPG, the Syrian wing of the PKK, which is recognised as a terrorist organisation by both countries.
Trump conflates the YPG with Syrian Kurds, a comment that is totally unacceptable to Turkey due to the three-decade terror campaign the PKK has waged against the country, causing thousands of deaths, including among Kurds.
Ankara has long been angered by Washington's alliance with the YPG to counter Daesh in northern Syria, and Trump’s recent tweet may have reignited tensions between the two allies, particularly as Trump's plan to call back US troops from Syria essentially relies on Turkey taking a lead in the fight against Daesh and other terror groups in the region.
“I think, at some point in the future, regardless of what the United States thinks or does, that Turkey will invade northern Syria,” said Edward Erickson, a former American officer and military analyst, who has written extensively on Turkish military history, from the Ottoman period to present times.
Erickson, whose most recent book, A Global History of Relocation in Counterinsurgency Warfare will be published in November, believes Turkish armed forces will replicate Operation Steel, the 1995 incursion of more than 35,000 soldiers into northern Iraq to hunt the PKK groups located there. This time, he said, the campaign will take place in northern Syria, with an aim to destroy the PKK-affiliated YPG sanctuaries and supply dumps.
“Like 1995, the operation will last several months and the Turks will withdraw. The American government and press will make lots of pro forma threats and condemnations, but they will stand by and let the Turks do as they please,” Erickson told TRT World.
In an apparent confirmation of Erickson’s observation, Turkey does not show any signs that it will surrender to US conditions formulated by Washington over its withdrawal.
On January 14, Turkey responded to the US president’s tweet.
“Terrorists can’t be your partners & allies. Turkey expects the US to honor our strategic partnership and doesn’t want it to be shadowed by terrorist propaganda,” İbrahim Kalin, the Turkish presidential spokesman, wrote on Twitter.
Kalin was one of the Turkish officials meeting with US National Security Advisor John Bolton last week during his visit to Turkey. Both men discussed delicate issues regarding the US withdrawal.
But right before the meeting, Bolton’s remarks in Israel triggered a perfect political storm in the Turkish capital, after he suggested that Washington would not leave Syria if Turkey sought to put the YPG in danger.
"We don't think the Turks ought to undertake military action that's not fully coordinated with and agreed to by the United States at a minimum, so they don't endanger our troops," Bolton said on January 6.
He also said that Turkey needs to meet Trump’s criteria and ensure the YPG-led Syrian Democratic Forces (SDF) that “have fought with us are not endangered."
Bolton, a neoconservative political operator, has staunchly defended American interventionism in the Middle East in the past, supporting both Iraqi invasion in 2003 and more US involvement in the Syrian civil war. He was also a strong defender of the Kurdish independence referendum in northern Iraq, held last year on September 25.
President Recep Tayyip Erdogan, feeling that Bolton was trying to dictate conditions to him, was quick to refuse an audience with the top US presidential adviser when he arrived in Turkey from Israel last week.
Later, he pointedly said that Bolton made a “serious mistake” by drawing parallels between the Kurds and the PKK-linked YPG. Some American policy-makers close to Trump also appear to agree with Erdogan, saying that Bolton crossed the line, which was “entirely unfortunate”.
Like Bolton's remarks, Trump’s tweet, which suggested even he is misconstruing the Kurds as the YPG, triggered concerns in Ankara. For many experts, Trump's statement had the potential to legitimise the PKK by seeking Turkey's assurity for the YPG’s safety.
Trump’s recent proposal of forming a "safe zone" between Turkey and the YPG is likely to cause scepticism in Ankara over Washington's real intentions for the future of northern Syria.
Trump’s safe zone vs. Erdogan's safe zone
The idea of creating a safe zone in northern Syria has recently been raised by Lindsey Graham, an influential Republican senator, after his meeting with Trump over the US pull-out in late December.
“They [the Kurds] stepped out nobody else would. He [Trump] is very aware of that problem. He’s going to be talking with Turkey, ensuring about Turkey that they would have a buffer zone they need, giving their concerns about YPG,” Graham said, using somewhat confusing terminology, which has become a norm for many US lawmakers and officials when it comes to the question of northern Syria.
The safe zone proposal was originally a Turkish idea raised by Ankara in late 2014 to address the growing refugee crisis and other issues, but the US rejected it.
With Turkey planning to conduct a third cross-border operation in Syria, Washington has now retrieved the idea of creating a safe zone, but with some differences to the one Turkey had proposed in 2014. The US is now advocating for a 30km buffer area between Turkey and the YPG in northern Syria.
After Trump’s provocative tweet, both the US and Turkish presidents have reportedly engaged in a telephone conversation. Both sides have indicated that the safe zone issue was one of the discussed ideas without specifying any agreement or disagreement on the proposition.
Ankara appears to have mixed feelings about the proposal, with concerns about how unsafe the safe zone could be for Turkey. Erdogan said he generally perceives Trump’s proposition “in a positive way.” But he outrightly rejected any presumption that the YPG could be part of the safe zone “project."
However, Trump thinks the YPG can still play a role in the proposed safe zone for the fight against Daesh.
“At first step, the safe zone could work for us. But in the long-run, it means the legitimisation of the YPG [by Turkey],” said Cevat Ones, the former deputy director of the Turkish national intelligence agency. 
“[If we fully embrace the idea], it means that we recognise the presence of the YPG in the east of the Euphrates,” Ones told TRT World.
Erickson agrees with Ones' safe zone assessment. “Such a safe zone [Trump's safe zone] might protect the YPG, but it could not protect Turkey,” Erickson said.
“The spatial characteristics of the area are too large for a safe zone. Which country would guarantee the safe zone? Who would pay for it? Which country would station troops there for an indefinite period? Consider also that terrorists can easily penetrate borders – just look at Gaza or the Indo-Pakistani border,” he added.
Russian mediation between the YPG and the Assad regime
There has also been a lot of talk about how Moscow, the main protector of the Assad regime during the brutal civil war, will react to a Turkish operation in northern Syria.
Some have suggested that Russia, which has not recognised the PKK - a Marxist-Leninist organisation - as a terrorist organisation, could play a mediation role between Assad’s Baath regime and the YPG.
During the Syria constitutional talks, Russia also appears to have accepted the idea of confederalism in Syria, like some in the US. The SDF and the YPG have strongly defended a Kurdish autonomous region in northern Syria and a federative Syria, much like its neighbour Iraq has.
“I do not think that Russia will broker a deal between Assad and the YPG. Creating disunity between the United States and Turkey is in Russia's best interests. If Russia does nothing, the Turks will conduct an incursion into northern Syria to eliminate the YPG. This will also damage US-Turkish relations,” Erickson commented.
“After securing the area and eliminating the YPG threat, the Turks will withdraw and turn the area back over to Assad,” he said, predicting the possible scenarios in northern Syria.
“This is a ‘win-win’ for Russia that costs them nothing and has a very high return on a minimal investment,” Erickson added.