A couple of years ago, the thinktank Policy Exchange argued controversially that the regeneration funds being pumped into declining Northern English cities should be stopped, effectively abandoning them to their fate. And just as Liverpool, Sunderland and Hull ponder their future, so a discussion on the problems of shrinking cities has emerged in countries as diverse as Germany, Russia, Japan and South Korea. In the US, of the twenty largest cities in the 1950s, no less than sixteen have shrunk. The term ‘urbicide’ was coined to describe the fate of the Bronx, the hollowed out neighbourhood associated with the dark days of 1970s New York. More recently the disassembly of Detroit has commanded attention, its abandoned structures testament to the loss of half the people who once lived there. Today, to the cheers of some who detested this sprawling monument to American industrial might, the Motor City appears increasingly unable, or unwilling, to resist the encroaching forces of nature, and sprawling vegation fills emptied-out factories.

As attention turns from boomtowns to doomed towns, and urban boosters lose out to purveyors of ‘creative shrinkage’, what’s behind the interest in ‘shrinking cities’? Why for example have artists, authors and filmmakers been so keen to record a requiem for Detroit, creating in the process a booming new cultural industry based on the imagery of urban decay? From Greek tragedies to the Grand Tour, ruins have long loomed large in the cultural imagination. Is it true, as one commentator alleges, that ruins are ‘good metaphors for human nature, for our ability to create and destroy’? Is a crumbling edifice an eyesore, or a healthy reminder that cities are mortal too?

‘Urban memory’ and industrial heritage have become big business. In Liverpool, the preservation of the industrial-era ruins of the Albert Docks was central to the city’s regeneration vision. Award-winning architects like David Chipperfield regularly incorporate traces of the past in their buildings of the future. Are these useful acts of preservation, or cynical attempts to create a feelgood factor? Is the rise of ‘ruin porn’ simply an aspect of Western decadence, with new, dynamic cities flourishing in places like China? Or does it reflect hard-earned wisdom and humility about our place in the world?