4 ideas
The category of the foreigner does not exist independently — a group defines itself as 'us' primarily by naming who counts as 'them.' Identity is therefore constructed by exclusion, meaning the stranger is not the opposite of the self but its necessary mirror.
When missionaries arrived they held the Bible and the locals held the land; after a shared prayer with eyes closed, the positions reversed — the locals held the Bible and the missionaries held the land. This compresses how ideological or religious cover can accompany and disguise material dispossession.
During WWI, ordinary civilians like painter Paul Cohen-Portheim were imprisoned in internment camps solely because their nationality matched a wartime enemy, absent any individual act. Legal-administrative categories can convert a peaceful resident into a threat overnight, based purely on group membership.
Societies exclude outsiders through repeatable, formal mechanisms — banishment, quotas, internment, deportation, denial of citizenship — rather than through spontaneous individual hostility. Mapping these methods reveals exclusion as an institutional toolkit that recurs across eras and governments.