This Article challenges the conventional narrative about the political question doctrine. Scholars commonly assert that the doctrine, which instructs that certain constitutional questions are “committed” to Congress or to the executive branch, has been part of our constitutional system since the early nineteenth century. Furthermore, scholars argue that the doctrine is at odds with the current Supreme Court’s view of itself as the “supreme expositor” of all constitutional questions. This Article calls into question both claims. The Article demonstrates, first, that the current political question doctrine does not have the historical pedigree that scholars attribute to it. In the nineteenth century, “political questions” were not constitutional questions but instead were factual determinations made by the political branches that courts treated as conclusive in the course of deciding cases. Second, when the current doctrine was finally created in the mid-twentieth century, the Supreme Court used it to entrench, rather than to undermine, the Court’s emerging supremacy over constitutional law. Under the current doctrine, the Court asserts for itself the power to decide which institution decides any constitutional question. With control over that first-order question, the Court can conclude not only that an issue is textually committed to a political branch but also that an issue is committed to the Court itself. This analysis turns on its head the assumption of scholars that the current doctrine is at odds with judicial supremacy. The modern political question doctrine is a species of—not a limitation on—judicial supremacy.