The date July 12, 2019, is likely to stay in the annals of Turkish diplomatic history. In the morning hours, two Russian transport planes delivered the first batch of components for the S-400 air-defence missile system to the Murted airfield on the outskirts of Ankara.

Procured from Russia, against vehement objections by the United States, the delivery seals security and defence ties between Moscow and Ankara. It also raises the risk of sanctions against Turkey, a key ally within NATO and long-standing US partner in the Middle East, the Black Sea area and in Southeast Europe. Ankara is facing a real threat of being ejected from the international consortium behind F-35, an advanced fighter jet which is set to provide the bulk of US airpower in the decades to come.