"One of the safest global cities in the world"

Mayor Khan is a slippery customer, and he used a slippery phrase in reassuring the public after Saturday's carnage: London, he declared, was "one of the safest global cities in the world". "Global city"? What is the difference between a "global city" and a mere city? The latter are more or less ethnically homogeneous places with insufficient vibrancy and diversity for the likes of Mr Khan. A "global city" is a microcosm of the global. Saturday's dead, for example, number four of Her Majesty's subjects (one English, one Canadian, two Australian) and three citizens de la république française. In part because of the socialist sclerosis of that republic, London has become home to one of the largest French populations on the planet. That's a "global city" - where an Aussie can head across London Bridge to a fashionable pub and fall into conversation with a charming demoiselle.

All these Canadians and Australians and Frenchmen were killed by a jihadist born in Pakistan, another born in Morocco, and a third from either Morocco or Libya. In London and the other "safest global cities in the world", a New Zealander can meet a nice Danish girl and be blown up by a Yemeni on the way home. The conceit of the global city is that there is no distinction between a Dane and a Yemeni.

In his new book The Strange Death of Europe, Douglas Murray returns periodically to a vital question: What happens when global cities become "global countries"? By 2011, "white British" were a minority in 23 of London's 33 boroughs. A similar transformation is well advanced in every city down the spine of England from Manchester and Leeds to Birmingham and Bristol, in all of which Islam is the principal source of population growth. For the most part, citizens of the new west accept that as a normal feature of life - while still expecting to find Cornish villages full of Cornishmen or Welsh market towns full of Welshmen. But soon we will have not just global cities but "global villages". Sweden, where most ethnic Swedes now alive will end their days as a minority within their own country, is already trending that way. A few months ago, I passed a pleasant few hours with a young couple who'd moved out of Östersund after a sexual assault by, um, "youths" and settled in a small town about an hour away in order to get away from the aggravation of said "youths". Not as easy as it was. They'd rented a place in a pleasant two-story apartment house only to find, as the chap put it to me, "I've got a f**kin' mosque in my basement." In a municipality of under a thousand people.