Days after Turkey launched a military operation against Kurdish fighters in northeastern Syria, NATO Secretary General Jens Stoltenberg warned Ankara against destabilising the region.
After meetings on Friday with Turkish officials in Istanbul, including President Erdogan, Stoltenberg stopped short at condemning Ankara's move, but said that the global efforts to put a stranglehold on ISIL could be "jeopardised" should the operation continue.
"Turkey is a great power in this great region, and with great power comes great responsibility," he said.
In response, Mevlut Cavusoglu, Turkey's foreign minister, said at a press conference alongside Stoltenberg: "Turkey has always been very sensitive about the civilians."
He lashed out at some members of the international community, include fellow NATO allies, which have criticised "Operation Peace Spring", saying: "They all know that the PKK and YPG are one and the same.
"On one hand you (the international community) are calling them terrorists and acknowledging our concerns and on the other hand you are not approving this operation. Turkey has tried its best to resolve this problem in the international community. And it had to do this because there was no resolution."
Stoltenberg is playing a weak hand. NATO cannot do anything beyond these verbal warnings.
Ankara began its long-threatened operation on October 9 in northeast Syria after US President Donald Trump on October 6 said American troops would withdraw from the region.
Turkey says it wants to create a 32-kilometre safe zone which would protect the country against Kurdish "terror" groups and ISIL, and where it could relocate Syrian refugees.
Ankara considers the Kurdish People's Protection Units (YPG) as an extension of the Kurdistan Workers Party (PKK), which has waged an insurgency against Turkey for 35 years and is designated a terrorist organisation by Turkey, the US and EU.
The YPG forms the main component of the Syrian Democratic Forces (SDF). The militia, a US ally, was crucial in the fight against ISIL, which is among the reasons why countries, bodies and rights groups have slammed Ankara's operation.
With Trump's lukewarm attitude to NATO having been publicly exposed over recent years, confidence in Brussels is low.
Stefano Stefanini, Italy's former permanent representative to NATO, told Al Jazeera that the alliance was effectively "powerless" in trying to manage Turkey's action in Syria, without US backing.
"Stoltenberg is playing a weak hand," he said. "NATO cannot do anything beyond these verbal warnings."
Stefanini added that NATO has before been challenged by Turkey, a member state he said was "acting against all the advice of other alliance members."
Turkey's border fears
NATO has previously had to assuage internal tensions between members, with military coups in Turkey and Greece as part of the Regime of the Colonels junta from April 1967 to 1974 and the Turkish military uprisings in 1960 and 1971 respectively.
Now, schisms between Turkey and other NATO members amid the current crisis are starting to surface.
For instance, Norway, Germany and the Netherlands have said they were suspending arms sales to Turkey.
And following Erdogan's threat that he may "open the gates and send 3.6 million refugees" into Europe, Greek Prime Minister Kyriakos Mitsotakis called on NATO to step up naval patrols in the Aegean Sea.
No action has been taken by these allies during all these years. It left Turkey no choice but to deal with the problem on its own.
Hacim Turker, senior researcher at the Ankara-based Bosphorus Center for Asian Studies (BAAM), told Al Jazeera: "Turkey does not have the luxury to turn a blind eye to the security issues along its borders.
"Turkey has the right to be supported by its allies in its endeavour to counter terrorism along its borders.
"However, no action has been taken by these allies during all these years. It has left Turkey no choice but to deal with the problem on its own."
With regards to NATO's stance, Turker said that it would be in the alliance's "best interest" to "refrain from alienating Turkey and acknowledge its security concerns."
Meanwhile, Lucia Yar, Turkey and Middle East Analyst at Comenius University in Bratislava, said Erdogan's advance into Syria will be perceived in Turkey as a greater priority than maintaining diplomatic relationships with Western allies.
"Domestic issues, including Kurds at the borders, take much higher importance among the public than Western-related cooperation," she said.
After the US withdrew its troops from the border area, it gaveTurkey responsibility for all ISIL fighters in the region.
Until now, the SDF had been working alongside the US military to maintain a stranglehold on ISIL in the region.
Stoltenberg's claim that ISIL could seek to capitalise on the lack of stability as a result of Turkey's offensive is logical, according to Paul Rogers, professor of peace studies at the University of Bradford and global security consultant with Oxford Research Group.
"In reality, the idea that [ISIL] ever went away is nonsensical. The group is still very much active, particularly in Iraq. It's perfectly reasonable to say that as a result of Turkey's intervention, we could see a resurgence of ISIL in that part of the world," Rogers told Al Jazeera.
"With everything that is happening, momentum is moving in the direction of ISIL," Rogers said, adding that it could lead to a more fighters in the area, akin to the 2013 al-Qaeda-claimed prison break at the Abu Ghraib facility in Iraq, in which hundreds escaped.
At the end of the day, Turkey's military intervention in Syria benefits Russia and this is a bad scenario for NATO.
Turkey's influence in NATO is considerable - it has the second-largest army in the alliance and is well-versed in Middle Eastern military operations, previously embarking on missions in northern Syria and campaigns against the PKK in its own country.
"Ankara seems to be aware of NATO's lack of leverage in this crisis and it is betting on this to advance its geopolitical interests, which currently diverge with those of the Atlantic Alliance," Eleonora Ardemagni, Gulf analyst at the NATO Defence College Foundation (NCDF) and associate researcher at the Italian Institute for International Political Studies (ISPI), told Al Jazeera.
NATO should be looking at how Turkey's advance impacts the region more widely, she said, because the intervention could ease the grasp on ISIL on the Syrian-Iraqi border, the group's "first hotbed".
"NATO, which has run a non-combat, training and capacity-building mission in Iraq since 2018 to prevent [ISIL's] resurgence through the empowerment of local security forces, has to keep a broader focus on what happens in this sub-region in order to elaborate its political options," Ardemagni said.
Russia treads carefully
Unlike the UN and EU, there is no mechanism in NATO to revoke a state's membership.
Any reform in this area could only be made possible by amending NATO's treaty - a move that would require unanimous support from members, something Turkey would never consent to.
As such, the lack of US support has exposed NATO's fragility in terms of its geopolitical clout and, without the certainty of Trump's backing, "the alliance loses its bedrock", Stefanini said, because the "US is really the only country that can put enough pressure on Erdogan."
Rogers, at the University of Bradford, said: "NATO can't control Trump, despite officials who work with the Kurds being livid at the fact that he has supposedly abandoned them.
"There is very little Stoltenberg can do."
In a further complication, the US will be aware of the importance of maintaining presence at the strategically located Incirlik Air Base in Adana, Turkey, which previously allowed the US to conduct bombing raids on Iraq during the 1990–91 Gulf War.
On the other hand, the potential involvement of NATO partner country Russia in the area may force the US to rethink its strategy, said Ardemagni.
For its part, on Thursday at the UN Security Council, Russia, along with the US, on Thursday vetoed a statement by France, Germany, Belgium, Britain and Poland condemning Turkey's operation.
Russian President Vladimir has said on the possibility of giving ISIL a second lease of life: "This is a real threat for all of us.
"How and where will they travel? Through Turkish territory, through other territories, further into Syria in uncontrolled territory, then through Iraq, other countries. We should understand this, know this, and mobilise the resources of our intelligence services to deal with this new threat."
On Sunday evening, under pressure from Turkey, Mazloum Kobani Abdi, the commander-in-chief of the Kurdish-led SDF, suggested he was prepared to strike deals with the Russian and Syrian governments.
His statements to media came as the Syrian army said it would deploy troops along the Turkish border to help Kurdish forces, a move signalling a major shift in alliances.
Ardemagni said: "Russia could enhance further its strategic influence in the sub-region, filling the American security vacuum and presenting itself as the first broker between the Syrian Kurds and the Assad regime.
"At the end of the day, Turkey's military intervention in Syria benefits Russia and this is a bad scenario for NATO."
