While the abstract equality of citizens before the law is imagined as protection from arbitrary, subjective legal judgments of an individual's character, I argue that judgments of character play a pivotal yet unexamined role regulating access to citizenship in American law. Through a comparative analysis of President Trump and President Theodore Roosevelt, I show how their seemingly personal obsession with libel law reveals a deeper interest in consolidating the state's power as sole arbiter of character in order to weaponize the “good moral character” requirement in immigration and naturalization law as an instrument of racial and ethnic exclusion.