Our familiarity with the phenomenon should not, though, lead us into contempt for the scale of the challenge. It has been estimated that as many as 800,000 new homes will be needed in the South of England in the next 17 years. Such demand is already putting huge pressure on greenfield sites and resulting in escalating property prices. Virginia Water, a prosperous suburb to the west of London currently playing host to General Pinochet, has seen prices double in three years. The average house in St John's Wood, north London, the most expensive district for housing in the country, costs more than pounds 400,000. Meanwhile it is possible to buy a terraced house in the North for pounds 20,000; homes change hands in pubs for a few hundred pounds, and residents are being stranded in worthless houses in districts where crime is rife.
Of course, one reaction to all this is to shrug and ask "so what?". If there is an "imbalance", then, so the argument runs, the market will correct it in due course. After all, during the recession of the early 1990s, the historic trend was reversed as the South suffered a much sharper correction to the boom of the 1980s than did the North. Negative equity was more familiar in Battersea than in Barnsley. There is no reason why the current Southern boomlet shouldn't burst and that Northern prices shouldn't recover, at least to some extent.
But even if the market were to work, it still cannot take account of the social costs of the depopulation of the North. We should not be afraid of saying that the creation of wastelands in poor parts of Northern towns and cities is something we can simply wait and hope for the market to address. There is a case for intervention to jump-start it. The creation of enterprise zones and infrastructure investment, in partnership with the private sector, was a formula successfully applied to London's Docklands. Next week, the Government's Urban Task Force, led by the architect Lord Rogers, will unveil its proposals for revival. Let us hope that its ideas are imaginative and that the Government, so soon after its poor showing in Labour's Northern heartlands in the European elections, will listen to them with some urgency.