Naturalisation, as it is called in political terms, or, more comprehensively, assimilation is a complex process of classification which has of course more than one end. […] Making citizens is an outlet for the energy of many groups of the native born. When the outlet is denied them, when foreigners are considered too disparate for assimilation to become possible or when immigrants have resisted assimilation en masse by living in segregated communities, the native born are gravely concerned. They feel thwarted and they look for relief. Restriction of immigration is one of their favourite self-relief measures.
