When I was studying medicine at the University of Glasgow, the economic historian Sydney Checkland published a book with the university press: it had the arresting title The Upas Tree: Glasgow, 1875–1975. In the spectacular nineteenth-century growth of the hundreds of malodorous, blackened and often squalid tenements (“closes”) that would house the workers who put their labour and lives into the industrial achievements of heavy engineering and shipbuilding, and the ensuing painful twentieth-century contraction of the “second city of the empire” under the sheer weight of the past, Checkland saw a paradigm for the decline of the United Kingdom as…