These are bold claims, amounting to a thesis that Britain has been wrecked and transformed from a familiar, law-abiding spot to an alien hell hole in just three or four decades. But here is an odd thing, surely: go back precisely three decades and you get to the summer of 1981, scene of some of the nastiest riots in modern British history, when racially charged violence saw tracts of Brixton in south London and Toxteth in Liverpool burn for days.

Seeking guidance, Bagehot decided to go off-line and read some books. From the shelves of the London Library, a gem: "Hooligan: A History of Respectable Fears" a calm and witty history of moral panics that have gripped England over the ages, published in 1982, and written by a Bradford University academic, Geoffrey Pearson (later at Goldsmiths). The book is out of print, so I trust I will be forgiven (not least by Professor Pearson) for quoting from it at length: it is a brilliant survey.

Just what happens if we take a time machine back three decades, to the time before the revolutionary transformation identified by Melanie Phillips?

Well, "Hooligan" records, you find front-page editorials like this one from the Daily Express of July 7th 1981, stating:

Over the past twenty years or so, there has been a revulsion from authority and discipline... There has been a permissive revolution... and now we all reap the whirlwind

You find editorials and columnists seeming to blame the decline on black immigration. Here is the Sunday Telegraph of November 29th 1981:

Brixton is the iceberg tip of a crisis of ethnic criminality which is not Britain's fault—except in the sense that her rulers quite unnecessarily imported it

Thanks to Professor Pearson's painstaking researches, the time machine can be ridden smoothly much further. At each stop, there are voices warning that the golden age of the past has been wrecked, and suddenly Britain is a dreadful place.