Under the American federal system, what happens to powers not expressly granted to the national government?

In the American federal system, powers that are not explicitly granted to the national government are reserved for the states, as established by the Tenth Amendment of the United States Constitution. This amendment clearly states that any powers not delegated to the federal government nor prohibited to the states are reserved for the states or the people. This principle reflects the federal structure of the government, where two levels of authority coexist, allowing states significant autonomy and authority to manage their own affairs.

By reserving these powers, the Constitution ensures a balance between national and state authority, enabling states to legislate and govern over various issues such as education, transportation, and law enforcement in a manner best suited to their specific needs and circumstances. This reservation of powers underscores the foundational concept of federalism in the U.S., promoting diversity of governance at the state level while still adhering to the overarching framework of national governance.