Citizenship is the political technology that divides humanity into members and non-members of a state. It grants rights to some and withholds them from others. Understanding citizenship requires understanding not just who belongs but why the boundary exists, what it costs those outside it, and who has historically been expelled from the category.
Under the Nationality Act of 1940, the United States created a new category of person: the citizen stripped of nationality for acts such as voting in a foreign election. In 1967, the Supreme Court struck that provision down in Afroyim v. Rusk, declaring citizenship a constitutional right that Congress could not take away. Between those two dates, people lost and recovered a status that determined whether they could work, travel, vote, or live securely within the country’s borders. Citizenship looks like membership. Its full meaning is visible only in its withdrawal.