Almost eight decades after the bomb, G7 leaders will meet in the Japanese city where survivors are urging action on disarmament amid the Ukraine war

A blow to the head probably saved Park Namjoo’s life. The 13-year-old schoolgirl, like many other children in wartime Hiroshima, was helping demolish buildings to make firebreaks in July 1945 when a piece of wood struck her on the head.

Less than three weeks later, at 8:15am on 6 August, a recuperating Park told her parents she still didn’t feel like going to school. As she and her younger brother and sister traveled on a streetcar near their home, the Enola Gay, a US B-29 bomber, dropped a 15-kiloton nuclear bomb on the city.