Turkish President Recep Tayyip Erdogan has declared his country is ready for a new military operation against the Syrian Kurds in the country's northeast. He made this comment as Turkish forces shelled the Syrian Kurdish People's Protection Units (YPG) in both the towns of Kobane and Gire Spi (Tal Abyad).

"We will destroy the terror structures east of the Euphrates River," Erdogan declared, reiterating a threat he's been making for weeks now. "We have completed preparations and plans regarding this issue." 

The recent cross-border shelling was the most significant attack Turkey launched against the YPG east of the Euphrates since Turkish warplanes bombed YPG positions near the town of al-Malikiyah on April 25, 2017. 

Ankara seems to be preparing for another ground incursion against the YPG, which will likely entail the forceful seizure of territory from the group. 

The likely target of an incursion will be Gire Spi since it has the most significant Arab population of any Syrian border region east of the Euphrates. Erdogan accused the YPG of afflicting ethnic cleansing on the Arabs of that town when the group initially captured it from ISIS in June 2015. That battle displaced thousands who fled across the border for sanctuary in Turkey. 

If the last two Turkish operations in Syria are anything to go by, Ankara will likely deploy its Free Syrian Army (FSA) proxies to help capture Gire Spi. Then it might garrison the region and resettle Syrian refugees currently in Turkey there in order to bolster its Arab-majority demographics, making it harder for the YPG to recapture in the long-term. 

After Turkey invaded the northwest Syrian Kurdish Afrin enclave early this year, it began settling displaced Syrian Arabs there in a clear effort to upend Afrin's long-established Kurdish-majority demographics. Given that Gire Spi is an Arab-majority region, Turkey would likely have a much easier job settling displaced Syrian Arabs there. 

However, unlike Afrin, Gire Spi is not isolated from the rest of Syrian Kurdistan (Rojava), but sits between Rojava's two largest and primary regions, Kobane and Jazira. 

Additionally, the US has relied on the YPG – and the larger Arab-Kurdish coalition Syrian Democratic Forces (SDF) – based in northeast Syria for its ongoing war against ISIS. This was not the case with the Afrin YPG, which the US never worked with. That was one major reason Washington did not raise any serious objections when Turkey invaded Afrin.

At present, the US is supporting the SDF in an offensive against ISIS redoubts in Deir ez-Zor, particularly around the town of Hajin. This operation has suffered several setbacks, with the SDF losing hundreds of fighters in battle. 

Were Turkey to pounce on the YPG in Gire Spi in the near future this could well divert the SDF/YPG's attention away from these important efforts against ISIS. The group has already temporarily halted its offensive as a result of Turkey's shelling. It previously diverted fighters from the ISIS war to try, in vain, to repel Turkey's invasion of Afrin. 

The US opposes such a development. In March 2017 it deployed troops to YPG-held Manbij to prevent clashes between that group and Turkish-backed FSA fighters. Washington invariably calls upon both sides to avoid clashing with each other and focus their respective efforts on destroying ISIS. 

In June, the US and Turkey implemented a roadmap deal to try and amicably resolve their disagreements over Manbij. Joint patrols between American and Turkish troops have just begun and could de-escalate the situation substantially. The prospect of any Turkish attack on the YPG in Manbij is therefore very unlikely at present. 

If the US, possibly alongside France, sends ground troops to the border in Gire Spi, as it did in Manbij, it could effectively deter a Turkish incursion there too and prevent the situation from degenerating into destructive all-out war. 

The latest Turkish shelling was completely unprovoked as was its invasion of Afrin earlier this year. Ankara has not divulged any concrete evidence proving that the YPG has ever launched cross-border attacks against Turkey, even during the aggressive invasion of Afrin in which Turkish forces killed several YPG members. Amid Turkey's latest attacks, the YPG is maintaining a defensive posture. 

Turkey has launched its two major ground operations in Syria to date in phases. By the time it completed Operation Euphrates Shield against ISIS in March 2017 it spent the next nine months consolidating the territory it captured. Then in January 2018, it launched its invasion of Afrin, the ludicrously named Operation Olive Branch. 

Incidentally, almost as much time has passed since the end of Olive Branch as passed between the conclusion of Euphrates and the launch of that Afrin invasion. Turkey began threatening and shelling Afrin intermittently from the summer of 2017 up until the beginning of the invasion last January. 

Ankara's recent shelling may indicate it has just begun a similar phase of cross-border bombardments rather than an imminent invasion.