Rafael Bardajl/The Spectator: A civilisation can be multiracial. History offers countless examples of societies composed of people of different ethnic origins who nevertheless shared a common language, civic culture, historical memory and political identity.
What no civilisation has sustained for long is multiculturalism understood not as diversity within a shared public culture, but as the permanent coexistence of parallel communities with no common civic identity. A democracy requires disagreement. A civilisation requires cohesion…