With a giant Stars and Stripes and two gleaming cars at his back, Joe Biden turned to focus his remarks on one member of the audience. “From my heart, I pray that your grandmom and family are well,” he told Rashida Tlaib, the only Palestinian American in Congress. “I promise you, I’m going to do everything to see that they are, on the West Bank. You’re a fighter.”

It was a characteristic peace offering by the US president, even as protesters rallied outside the Ford plant in Dearborn, Michigan, and Tlaib herself challenged Biden over his unyielding support for Israel. But Tuesday’s gesture, and even a Middle East ceasefire declared on Thursday, may not be enough to heal a growing rift in the Democratic party.

Biden’s first hundred days as president were striking for their rare display of Democratic unity, pleasantly surprising the left with his ambitions for government spending, racial justice and the climate crisis. Alexandria Ocasio-Cortez, a congresswoman from New York, said his administration “definitely exceeded expectations that progressives had”.