Exactly five years ago, BNP Paribas announced it was freezing some of its investment funds because it could not value them properly. It was the first boulder in an avalanche that culminated a year later in the collapse of much of the world’s banking system and the worst recession for 80 years.

Those five years have seen nearly every government in the West displaced by unforgiving electorates. There have been remarkable policy measures: central banks have lowered interest rates effectively to