What happens when a state law conflicts with federal law?

When a state law conflicts with federal law, federal law prevails due to the supremacy clause, which is found in Article VI, Clause 2 of the United States Constitution. This clause establishes that the Constitution, federal laws made pursuant to it, and treaties made under its authority constitute the supreme law of the land. When there is a conflict between state and federal laws, the federal law takes precedence, meaning that the state law cannot be enforced if it contradicts federal regulations. This principle ensures a consistent legal framework across the country, preventing states from creating laws that could undermine federal authority or lead to a patchwork of conflicting regulations.