“We heard the shelling, we heard the bombing—they [injured patients] came in by the hundreds, walking and running, in private cars and ambulances, and it went on for three weeks,” remembers the Norwegian doctor Mads Gilbert, who took off for Gaza as soon as he heard that the Israeli assault had started at the end of December last year.

At a talk in London he shows a video clip of a mass of frightened people converging on Al Shifa Hospital, carrying their injured loved ones, shouting and jostling to get them through the doors as quickly as possible.

Inside the draughty hospital—its windows blown out by the Israeli bombing of a nearby mosque, its basic medical supplies exhausted by the long siege of Gaza—surgeons worked ceaselessly, sometimes two or three to an operating room. “All the time we heard the drones—one, two, three at a time, 24 hours a day,” he …