When I visited Hiroshima in 2003, what initially struck me was the apparent normality of the place — it seemed a busy Japanese city almost like any other. It is, and it isn’t.

A tram took me from the rail station to the Peace Park — just over the river from the ruined dome you see in so many photographs. As I sat under the trees, Japanese school students gathered my views about atomic weapons for a survey. Walking through the park you pass a grass-covered mound, two or three meters high — containing the unidentifiable ashes of some seventy thousand human beings. And to get to the park, I had walked across the unusual T-shaped bridge by the tramline from the railway station, the bridge which was the aiming point for the first atomic bomb, Little Boy, dropped on that hot summer morning in 1945.

Hiromu Morishta was seventy-three when I interviewed him, and fourteen on the day of the bombing, a patriotic student in junior high school. He and his classmates believed the statements from the military high command that Japan was winning the war, even though no one had enough to eat. His mother, starving herself to feed her children, was more sceptical. The high school students no longer attended lessons but worked in a factory making guns and aeroplane parts.