Article 19 TFEU's unanimity requirement shares a striking similarity with a two-century old debate on voting and minority rights between the ‘father’ of the US Constitution, James Madison, and the ‘rebellious son’, John C. Calhoun. Madison made majority voting a necessary condition for impartial lawmaking and minority protection in multistate unions. Conversely, Calhoun sought to maintain the racial status quo through advocating for a competing unanimity-based structure. Minority protection in Article 19 TFEU aligns with Calhoun's model. This Article reassesses Article 19 TFEU through the foundational principles of constitutionalism underlying the US debate and shows their continued relevance for contemporary case law and minority protection in the EU. Particularly, it demonstrates, first, that Article 19 offends the impartiality principle of nemo judex in causa sua—no person should judge their own cause—which has long been a leitmotiv in Western constitutional theory. Second, it illustrates that unanimity causes de jure and de facto ramifications for ethnic and religious minorities in the EU. Last, the Article provides a theoretically grounded and comparatively informed argument to aid ongoing attempts for treaty amendment.