The United States Constitution’s citizenship rule, which grants citizenship to, among others, the American-born children of illegal aliens, has come under attack. Professor Eisgruber defends the Constitution’s birthplace rule against calls for its amendment and against arguments in favor of a parentage rule. He proposes the Responsiveness Principle as a competitor to a consent or reliance theory to provide the normative justification for a rule of citizenship. Under this principle, a government should be responsive to the interests of all those over whom it exerts general jurisdiction. Professor Eisgruber argues that the current birthplacerule is the best way to implement the Responsiveness Principle because it makes it likely that those subject to the laws will have an effective voice in determining their content. He also cautions that an amendment modifying the birthplacerule would likely affect the interpretation of other constitutional provisions by compromising the Constitution’s commitment to political justice.