At a glance, 'borders' and 'boundaries' may seem synonymous. But in the real (geopolitical) world, they coexist as distinct, albeit overlapping entities: the former a state's delimitation of territory; the latter the social delineation of differences. The refugee crisis in Europe showed how racial and ethnic boundaries are often instrumentalised to justify the strengthening of state borders - regardless of the cost in human life. But there are other,...