Specifically, a smart city happens when three specific networks interact: the communications grid, the energy system and the so-called “logistics internet” – which can track people and things through transport and supply systems.

But there’s a problem: who controls the project and who owns the data it generates? We live in an age when your supermarket’s software knows who you are from your buying choices; where your email provider can send you advertisements matched to key words in your supposedly private messages. But issues raised by smart cities go beyond privacy – they raise problems for democracy and control.

More than 2.5 billion people, mostly urban dwellers, voluntarily wear a tracking device – their smartphone. It can tell you the nearest coffee shop, order you a taxi and even find you a nearby potential sex partner because it knows where you are. Hire a bike and the city transport system knows where you start and finish. The privacy issues here are dealt with by limiting the flow of data between public and private sectors, and by making the individual the centre of the information flow.

But in a smart city, you need data to flow freely across sectors that, in the commercial world, would normally be separate. The energy system needs to know what the transport system is doing. And the whole thing needs to be run like a “God game”: the city government, not the individual, must exercise control.

For this reason, early on, the technology companies realised smart could only be built with a new kind of city government.