Of the many divides revealed by Britain’s Brexit vote, the cities-versus-the-rest divide was one of the widest. In London, Manchester, Liverpool, Glasgow, and Cardiff, strong majorities supported staying in the European Union, while more suburban and rural areas were far less supportive. In general, population density –a proxy for urbanity–was a good indicator of the way people would vote.

Those voting Remain tended to be younger, richer, and better educated, and they tended to live in cities. To many in their 20s and 30s, the rhetoric of the Leave camp was depressing and anachronistic. They didn’t identify with its anti-immigration message, or with the nostalgia for a time when Britain was less diverse, whiter. These Londoners want Britain to be like London–a melting pot–and that means being part of the EU, not some little island with a little island mentality.

The question is whether Britain’s city-versus-the-rest divide points to a wider phenomenon in the world, and perhaps even the possibility that cities could break away from states in the future. At the moment, the possibility of London leaving Britain is remote, of course. But it’s also not fanciful either. In a poll following the result, one in six Londoners aged 18 to 24 said they supported forming an independent country. And, indeed, you might say London would make a better go of it than, say, Scotland. Certainly it has more money and better infrastructure.

Historians will tell you that cities are a more durable form than nations in any case. Cities like Stockholm, Cologne, and Bruges were great trading centers long before Europe’s “springtime of nations” in the 19th century. The preeminence of the city is therefore a return to the old order, not a complete rupture with the past. As the journalist Christopher Beanland says in an article for the online magazine The Long+Short, new city groups like the Global Parliament of Mayors are reminiscent of past urban powerhouses like the Hanseatic League, which dominated Europe from the 15th to the 19th century (or, at least, they have potential to be).

Beanland quotes Cristina Ampatzidou, editor-in-chief of Amateur Cities, a “city-making” publishing platform in Rotterdam: “It is often said that great cities survived great empires. So it is not unrealistic to think of cities as discrete entities that compete and collaborate with each other, independently from the states to which they belong.”

“States will not vanish or surrender their waning sovereignty,” veteran urbanist Benjamin Barber says in the same piece. “But [they] will meet across frontiers and work together to solve problems. The objective is not an independent London or New York, but interdependent cities collaborating globally. And that is happening.”

There are many city-states already, including Singapore, Hong Kong, and (arguably) Dubai. They tend to be successful and outward-looking and have great airports. “It’s the airlines of each of these (Singapore Airlines, Cathay Pacific, Emirates and Etihad) that open up each respective city to the world in the way that the machinery of the Hanse did on the Baltic Sea 600 years ago,” Beanland says.