Nation states cause some of our biggest problems, from civil war to climate inaction. Science suggests there are better ways to run a planet

Map: Norman Kirby; Photograph: Tatsuro Nishimura

Try, for a moment, to envisage a world without countries. Imagine a map not divided into neat, coloured patches, each with clear borders, governments, laws. Try to describe anything our society does – trade, travel, science, sport, maintaining peace and security – without mentioning countries. Try to describe yourself: you have a right to at least one nationality, and the right to change it, but not the right to have none.

Those coloured patches on the map may be democracies, dictatorships or too chaotic to be either, but virtually all claim to be one thing: a …