International human rights law guaranteed the ‘right to a nationality’ following the World Wars, reinforcing the assumption that legal nationality was a social good that guaranteed political membership and rights protection. Yet today we see troubling shifts in how states view citizenship and nationality rights; at the individual level, denationalisation (the involuntary loss of citizenship) is increasingly used as a method to punish enemies and reward others, thus de-valuing the concept of citizenship as a fundamental right and instead positing it as a privilege. At the group level, denationalisation sometimes targets entire identity groups in the quest to create and isolate ‘strangers’, particularly in times of rising nationalism. In this chapter, Lindsey N. Kingston challenges the belief that legal nationality is always a social good and contends that legal nationality – the assumed marker of political membership in our world system – can be weaponised. First, modern citizenship and its ensuing documentation exist in many communities with deeply harmful consequences. Second, citizenship is approached by some political leaders as both a reward for exceptionally good deeds and a punishment for bad behaviour deemed threatening to the state. Third, the statelessness that results from the revocation or denial of citizenship serves as a method for the erasure of specific identity groups.