There was a moment a few years ago when Britain seemed to have turned the tide of history. A middle-ranking power had reclaimed the self-confidence and sense of place that had mostly eluded it since the curtain had fallen on empire.

The economy was open, vibrant and competitive. London buzzed as a global hub for financial services and a second home for the newly rich of the world's rising nations. Tony Blair's centre-left government used buoyant tax revenues to repair and update the nation's public realm.

The essence was that the country could have it both ways: a liberal market economy where the rich got ever richer alongside modern, well resourced public services and welfare. The doors were opened to eager immigrants. The universities flourished. With success at home came status abroad. Britain regained a place at the top table.