One morning last month, while I was waiting at a bus stop on the western edge of the western Ukrainian city of Lviv, I struck up a conversation with a man in his early forties named Mykola Hryhoryan. Across from the bus stop was a bombed-out museum. I asked if he knew what had happened to it. "It was hit by a Russian drone," he said. Mykola was wearing jeans and a black parka with the hood pulled over his head. He told me that he was a soldier.

Sumy is busy enough during the day, with shops open and well-stocked. But once it gets dark the streets are almost deserted. Air raid alerts come frequently. Anti-aircraft guns fire tracer into the sky for hours, aimed at the waves of Russian drones that cross the border near here to attack targets much deeper inside Ukraine – and sometimes in Sumy itself. A big block of flats has a hole three storeys high ripped out of it.