The post-Brexit debate, often involving the performance of allegiance on Facebook or Twitter, does not much resemble the collective deliberation of the ancient agora. Other aspects of the ancient city are making an unwelcome return. The first is a more prescriptive ideal of citizenship, according to which those who fail to measure up to a patriotic standard – ‘Remoaners’ and immigrants – lose their moral claim to membership. The ancient punishments of ostracism and exile are reprised in the enthusiasm of the Home Office for deporting people to countries they’ve never seen. Meanwhile, productive work on farms and in factories is often delegated to rightless foreign metics.