David Runciman · Invented Communities: post-nationalism

What is wrong with the idea of a world state? John Rawls, the world’s most celebrated living political philosopher, believes that the answer is relatively straightforward. ‘I follow Kant’s lead in Perpetual Peace,’ he writes, ‘in thinking that a world government – by which I mean a unified political regime with the legal powers normally exercised by central government – would either be a global despotism or else would rule over a fragile empire torn by frequent civil strife as various regions and peoples tried to gain their political freedom and autonomy.’ Which is to say: size matters. Or, as Kant wrote, ‘laws always lose in vigour what gov…