When the ground shook off Iwate prefecture at 9pm on Wednesday, the magnitude 6.0 jolt – the latest in a series of sizeable tremors – barely registered in a country still mopping up after two powerful typhoons and bracing for a fresh bout of torrential rain and landslides. Natural disasters have long been a fact of life in Japan, where schoolchildren rehearse earthquake evacuations the way other nations hold fire drills. Every September 1, in a ritual as much of collective memory as civil...