In today's world, people speak more than 6000 languages and identify with thousands of cultural groups and a large variety of different religions. Despite such a number of differences, these and other features of human diversity are housed politically, inside roughly 200 nation-states. Thus, the contemporary reality of human diversity far exceeds the number of nation states in the current international order. Globally speaking, a diverse citizenry is an unavoidable fact for most countries across the planet. Additionally, developments such as transnational migrations, rising socio-economic...