Final answer:
The Supremacy Clause of the Constitution asserts that federal laws and the Constitution are the supreme law of the land, taking precedence over conflicting state laws.
Step-by-step explanation:
The Supremacy Clause of the Constitution means that federal law, including the Constitution and treaties made by the federal government, is the supreme law of the land. When federal and state laws conflict, the national law prevails, as long as it is within the national government's constitutional authority. This principle was established and affirmed by the landmark Supreme Court case of McCulloch v. Maryland in 1819, which also reinforced the doctrine of implied powers, allowing Congress to enact laws deemed necessary and proper to exercise its enumerated powers.