Answer: The Supremacy Clause of the Constitution of the United States
Explanation: (Article VI, Clause 2), establishes that the Constitution, federal laws made pursuant to it, and treaties made under its authority, constitute the "supreme Law of the Land", and thus take priority over any conflicting state laws.
Our cherished Bill of Rights, which turned 225 years old this month, is one of the great oddities of American constitutional history. What began as a mere afterthought to the Constitution ended up saving the Constitution from its Anti-Federalist critics, and today looms larger in the American mind than the Constitution itself.
