In the aftermath of Turkish airstrikes on Kurdish positions in north-east Syria last week, US troops escorted an ageing militant through an angry crowd to inspect the damage. As a senior leader of the Kurdish militant organisation the PKK, Abdi Ferhad Şahin, known as Şahin Cilo, has a $1.1m Turkish government bounty on his head. Cameras were present to record the moment, which amounted to Cilo’s remarkable transformation from hunted to courted. Despite being proscribed as a terror group by Washington and Ankara, Cilo’s forces have become ever more central to Washington’s war against Islamic State (Isis) in Syria. So much so that Cilo’s appearance alongside troops who not long ago might have seized rather than protected him seemed to be worth the price of angering an ally. Here, the most complicated corner of the war in Syria looks certain to get messier. US armoured vehicles were deployed over the weekend along a section of the tense Turkish border, creating a buffer zone between the Turks to the north and Kurdish forces to the south, who are known in Syria as the YPG and are closely linked to the PKK. Despite increasing Turkish rancour, Washington continues to see the Kurds as an indispensable ally in the next phase of the Isis campaign – the push towards Raqqa. In Turkey’s eyes, the Trump administration was supposed to change all that. Anger at Barack Obama’s policy of using the Kurds as US proxies had given way to hope that the new president would either send US forces to do the job, or switch loyalties to localised Arab units, which Turkey is trying to raise. With the US-Kurdish pact consolidating, not weakening, the Turkish president, Recep Tayyip Erdoğan, has reverted to claiming that the burgeoning alliance could end up empowering a Kurdish push for autonomy, and stoke the fires of insurgency inside Turkey’s own borders. When Turkey launched the pre-dawn airstrikes on Tuesday, the US was given just 52 minutes’ warning. Asked about the images of Cilo under US escort, state department deputy spokesman Mark Toner said: “I haven’t seen those pictures, but I would strongly call into question... that senior military leaders of the US were somehow glad-handing or shaking hands with PKK leaders. As I said, the PKK is a recognised foreign terrorist organisation by the United States.” The denial underscores the dilemma for the US, which has been criticised by both allies and proxies for not having a coherent strategy in Syria or Iraq and, almost three years into the war with Isis, for not being able to finalise the fighting force that will end up storming Raqqa, or define a path for what may follow. Washington has sent more than 500 American special forces and advisers to assist the Syrian Democratic Forces, an umbrella group led by the YPG, which includes some Arab units. Many YPG leaders are former PKK commanders who honed their skills fighting the Turkish army for decades. In Iraq, at least 5,000 US troops are advising the Iraqi army in the fight against Isis. The centrepiece of that war – the push to retake Mosul – has ground into a seventh month, with airstrikes failing to dislodge determined militants in the west of the city. After Mosul will likely come a push towards Mount Sinjar, the spiritual home of Iraq’s Yazidi sect. Hundreds of thousands of Yazidis were driven from the town of Sinjar and the surrounding area by Isis in August 2014, and many of the sect’s female members were enslaved. Kimberley Taylor from Blackburn is part of the all-female Kurdish force battling to rout Islamic State. Driving them on is the chance to free women enslaved by the extremists: ‘It starts with fighting Daesh, then the mentality of the male’ Turkish jets also attacked Sinjar mountain last week, killing five peshmerga fighters loyal to the Kurdistan Regional Government (KRG) – an ally of Ankara who retook the city of Sinjar in November 2015. The attack targeted PKK positions on the mountain that have been consolidated over the past year. As it works to complete the first phase of a 911-kilometre, three-metre high wall along its border with Syria, Turkey is putting pressure on the KRG to restrict the movement of the YPG and the PKK in Sinjar. In another sign of cascading fallout, this has sparked clashes between the peshmerga and PKK affiliates. But a regional military source has said Turkey is determined to step up its disruption of US plans, having given up on hopes of a wholesale policy shift in Washington away from collaboration with the PKK. “They were happy when [CIA director Mike] Pompeo came to Ankara and told [Erdoğan] that the Kurds would only isolate, not capture, Raqqa. That bought time, but that time has now elapsed and what you will see is a more aggressive posture by the Kurds. I don’t rule out a ground incursion towards Sinjar. And if that happens, the Americans have said they will not stand in their way.