Apps and booklets are offering advice on how to build a bunker, stockpile food and live without electricity in case the worst happens

Germany is developing an app to help people locate the nearest bunker in the event of attack. Sweden is distributing a 32-page pamphlet titled If Crisis or War Comes. Half a million Finns have already downloaded an emergency preparedness guide.

If the prospect of a broader conflict in Europe seems remote for many, some countries at least are taking it seriously – and, in the term used by Germany’s defence minister, Boris Pistorius, taking steps to get populations kriegsfähig: ready for war.