Barely a month after the traumatic July 15 failed coup attempt, Turkey launched a military operation in Syria last week.

Supported and armed by Turkey, Free Syrian Army units swiftly took control of border town Jarablus, pushing the Islamic State of Iraq and the Levant (ISIL, also known as ISIS) southwest towards al-Bab region and advancing towards the south and west.

At the outset, the United States verbally supported the operation. In fact, according to one report, the Pentagon even offered Turkey the possibility of a joint operation with the participation of 40 US commandos, a plan that was allegedly shelved as a result of the White House's slow response. But nevertheless, the US was supportive of the operation in its initial stages.

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US officials called upon the Syrian Kurdish People's Protection Units (YPG), the Kurdistan Workers' Party's (PKK) sister organisation in Syria, to withdraw to the east of the Euphrates river and threatened to withhold support should they not comply.

As time went on, the US has, however, changed the tone, calling on Turkey to refrain from clashing with the YPG and instead has begun urging it to focus on the common enemy, ISIL.

Both US Defense Secretary Ashton Carter and the White House have expressed their displeasure with Turkey's targeting of YPG forces.

By August 30, the US claimed that it has reached a "loose" agreement to stop fighting between Turkish forces and the YPG-dominated Syrian Democratic Forces (SDF) coalition, a claim that was vehemently denied by Turkish officials.

The rationale behind the operation

Turkey seems to have four goals in mind in carrying out this operation.

First, it wants to prevent the Democratic Union Party (PYD) from establishing territorial contiguity between its cantonsThe last remaining gap in PYD-held territory on the Turkish border lies between Kobane and Afrin, and forms the strategic objective of this operation.

The second goal of the operation is securing the Aleppo corridor from belligerent forces, be it YPG or ISIL.

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Third, Turkey aims to clear the ISIL presence, which has posed a direct security and strategic threat to Turkey, from its borders.

Fourth, by clearing ISIL from the area and halting the YPG's westward expansion, Turkey aims to create breathing space for the Syrian opposition, which previously was squeezed between ISIL, the Syrian regime and the YPG.

The scorecard

Turkey's move has effectively halted the YPG's westward expansionBefore the operation the YPG was hoping to connect its Kobane and Afrin cantons and hence creating a linked-up statelet on the Turkish border. This was a prospect that Turkey had long denoted as its red line, inviting military intervention.

On top of this, US Secretary of State John Kerry and Russian Foreign Minister Sergey Lavrov met on August 26 to discuss the Syrian issue.

While offering a glimmer of hope for a political settlement, both figures have explicitly said that they will not support Kurdish independence in Syria, emphasising instead the need to maintain the country's territorial integrity.

Despite the US' appetite for placating Turkey to dampen skyrocketing anti-Americanism caused by the widespread belief that they were either involved or at least informed about the coup, Americans aren't ready to sacrifice the PYD.

 

Although there was nothing new about this point, the preservation of Syria's territorial integrity has now become everyone's official stance, including the PYD's. Turkey in turn has lauded this reflection of its official stance by Russia and the US.

Yet, as the Pentagon and White House have emphasised, Turkey and the US still take very different positions on the PYD/YPG.

While the YPG's territorial ambition is causing trouble for US foreign policy, Americans are not ready to give up on the YPG. They see a role for the group not just in the war against ISIL, but also in post-crisis Syria.

The limits of Kurdish ambitions

The Kurds are experiencing the limits of their alliance. The Russian stance on Turkey's incursion into Syria illustrates that previous Russian support for the PYD was instrumental and motivated by the dynamics of the Turkish-Russian dispute.

Once both countries mended their ties, the PYD's value for Russia declined significantly, but not completely.

The events of the past week have also shown that sympathising with the Kurds - mostly for their secular political disposition - and forming pragmatic partnerships with them in the fight against ISIL or in "tamingTurkey, is not akin to forming strong alliances.

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Despite initial appearances, of all the main groups in Syria, the Kurds are the one to lack a committed ally.

The debate in the run-up to the Geneva III talks has clearly confirmed this point. Once Turkey put up strident opposition to the PYD's participation into the talks, none of the Kurds' alleged allies proved to be adamant on their inclusion.

Despite the US' appetite for placating Turkey to dampen skyrocketing anti-Americanism caused by the widespread belief that they were either involved or at least informed about the coup, Americans aren't ready to sacrifice the PYD.

Conflicting stance

The US is forcing the PYD to tame its ambitions, but it doesn't want to alienate the PYD completely. Several warnings from the White House and the Pentagon demonstrate this point.

US President Barack Obama's special envoy for the global coalition to counter ISIL, Brett McGurk, has tweeted saying: "We want to make clear that we find these clashes [between Turkey and the YPG] - in areas where ISIL is not located - unacceptable and a source of deep concern."

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On one level, this reveals conflicting institutional stances in US policy regarding the YPG's role as a fighting force against ISIL and its place in its overall Syria strategy.

On the other hand, this shows that the US is trying to tread a fine line between its partnership with the YPG and relations with its longtime NATO ally Turkey.

While the US has repeatedly urged the YPG to withdraw to the east of Euphrates, it hasn't problematised the PYD's acquisition of land within a civil war context.

Moreover, the US is trying to draw a line to limit Turkey's military operation, reducing the prospect of direct clashes between Turkey and the YPG.

Indeed, all of the statements coming from the US show that it is not problematising the legitimacy of the PYD's grip in the areas such as Afrin and the east Euphrates.

This is important. Because it shows that the US does not anticipate a highly centralised unitary Syria in the future.

Rather, it sees the end game as a highly decentralised but nominally unitary state. As a corollary, it sees a role for the PYD and SDF in post-crisis Syria.

Galip Dalay is a senior associate fellow on Turkey and Kurdish Affairs at the Al Jazeera Centre for Studies, and research director at Al Sharq Forum.

The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy.

Source: Al Jazeera