What court case is known for proving the US Constitution the supreme law of the land?

The Supremacy Clause in Article VI of the US Constitution explicitly states that the Constitution, treaties and Federal Laws "...shall be the supreme Law of the Land."

McCulloch v. Maryland, (1819), is credited as the first US Supreme Court case that emphasized the supremacy of constitutional authority over state law, when the Court upheld Congress' right to charter a national bank to handle its financial transactions, and overturned a Maryland law taxing the bank because it wasn't state-chartered.

Chief Justice Marshall wrote that the states could not tax the federal government, and that the "power to tax is the power to destroy."

McCulloch signaled the beginning of an ongoing struggle for control between the states and federal government. During Chief Justice Marshall's tenure on the Court, most (but not all) decisions supported federalism.

Case Citation:

McCulloch v. Maryland, 17 US 316 (1819)

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