Washington’s top diplomat will discuss the Gaza war with Turkey’s mercurial leader on Saturday before flying to Crete to address Greek worries about the looming sale of US fighter jets to Ankara. US Secretary of State Antony Blinken arrived in Istanbul late on Friday for the first leg of a trip that includes visits to Israel, the occupied West Bank, and five other Arab states. Blinken’s fourth crisis tour since the start of the Gaza war three months ago comes with fears mounting that the conflict will engulf swathes of the Middle East. Israel’s war on Gaza has so far killed 22,600 people and s…