The air strikes had been far more significant than anything previously visited by the Turks on the YPG, the Syrian Kurd fighting group that has become the Americans’ primary ally in the forthcoming battle to capture the city of Raqqa from Isis. Operations to shape the battlefield around the militants’ capital are ongoing, and some sections of the front YPG units, the mainstay of the anti-Isis alliance, are now less than four kilometres from the outskirts of Raqqa.
However, the entire operation was thrown into jeopardy early on the morning of 25 April, just days before US officials confirmed that President Donald Trump had authorised the direct supply of weapons to the YPG. Turkish jets repeatedly bombed the YPG’s main command centre on Qarachok Mountain, just above the small town of Derik, destroying ammunition stocks, a communications centre and accommodation blocks. The dead included Mohammed Khalil, a top commander involved in planning the Raqqa operation.