Did the Framers attempt to establish an effectual power in the national judiciary to void state law that is contrary tofederal law, yet permit Congress to decide whether or not to confer federal jurisdiction over cases arising under federal law? Does the Constitution, then, authorize its own destruction? This Article answers yes to the first question, and no to the second. Based on a new study of the meticulously negotiated compromises that produced the texts of Article HI and the Supremacy Clause, and a new synthesis of several classic Federal Courts cases, the Article shows that, by self-conscious constitutional design, and by dint of a consistent pattern of constitutional interpretation by the Supreme Court, the principal mechanism f...