What does the Tenth Amendment suggest about the powers of U.S. states and the federal government?

The Tenth Amendment to the U.S. Constitution clarifies the division of authority within the American federal system by establishing that powers not delegated to the federal government, nor prohibited to the states, are reserved to the states or to the people.12

This amendment functions as a foundational principle for states’ rights advocates, emphasizing that the national government possesses only those powers specifically granted to it by the Constitution, either expressly or by implication. Conversely, the states retain all other "residual" or "reserved" powers, allowing them to maintain their own laws and policies provided they do not conflict with federal authority.12

While the amendment does not grant states additional powers or alter the fundamental relationship between the state and federal governments, it serves as a critical constitutional check. Throughout American history, it has been central to debates regarding the limits of federal authority, particularly in areas such as taxation and the regulation of commerce.12