War is now a possibility in Norway, by the prime minister’s own admission. The country, which borders Russia, has gone into “total defence” mode, preparing its population for the worst in light of the fighting in Ukraine. Dug beneath a peaceful park, the St. Hanshaugen air raid shelter, one of Oslo’s largest, can take in 1,100 people behind its heavy metal doors if ever the worst comes to pass. The air is chilly, the lights dim, and the toilets basic: it is far from cosy, but it is designed to...