Modern citizenship—understood in terms of the formal legal distinction between “citizen” and “alien”—functions as a barrier to the individual's territorial rights. In other words, it determines whether a given individual does or does not enjoy unimpeded rights of access to, and presence within, the territory that the state calls its own. In this capacity, it is wielded efficiently, systematically, and even brutally against individuals who seek to fashion better lives for themselves by moving into, or remaining within, the territories of states other than their “own.” In the contemporary West, entirely as a matter of routine, millions are kept out of, and removed from, the territories of states on the ground that they are not citizens of the states in question.