There were a couple of moments during Boris Johnson’s Manchester speech on Saturday when I had to wonder if the new prime minister had been reading Jane Jacobs.

He was talking about how London had turned itself around from the decline of the 1960s and 70s to regain its position as a world-leading city.

He identified the four basic ingredients of success as liveability, connections, culture and, finally, devolved power and responsibility.

Liveability required safe streets, affordable homes, good jobs and great public services, he said, while connections boiled down to broadband and transport. “Inspiration and innovation, cross fertilisation between people, literally and figuratively, cannot take place unless people can bump into each other, compete, collaborate, invent and innovate,” said Johnson.

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