If you were trying to escape political news this week you might have settled on the RSPB’s latest survey of amphibians, revealing a sharp drop in the numbers of frogs and toads observed in domestic gardens over the past four years – as our gardens are built on or paved-over. Either that or figures from the Centre for Cities, a think tank which has quantified the revival of English city centres over the past 15 years. The population of inner Liverpool is up 181 per cent, that of inner Birmingham 163 per cent and Manchester 149 per cent.

But don’t think you were escaping from politics by reading this – these are stories with political implications, too, especially for the Conservative Party. They speak of demographic and cultural changes which risk undermining a good part of the traditional Tory vote.

Thirty years ago, when I read geography at university, cities were studied like molecules. In the middle was a central business district, full of shops but where hardly anyone lived. This was surrounded by a ‘twilight zone’ where the poor were housed on rotten, crime-ridden and jobless estates, or in bedsits carved out of faded, once-middle class houses. As you moved outward, the better life became. The outer suburbs were the places of success, of golf clubs, large gardens and, increasingly, gated estates. It was an environment where the private car dominated and where you could live, if you wanted to, without meeting your neighbours – a place which nurtured and encouraged individualism.

Things were never quite as defined as the molecular geographers would have it. In London, for example, Belgravia never fell out of favour with the rich, and neither did Edgbaston in Birmingham. But there was a lot of truth in it. The term ‘inner city’ was synonymous with social problems. The well-off lived amongst nature on the fringes of urban areas; the poor in dust and grime in the thick of them.