A governmental system in which authority is divided between two sovereign levels of government: national and regional.
The supreme (or ultimate) authority to govern within a certain geographical area.
A governmental system in which sovereignty is vested entirely in subnational (state) governments.
A governmental system in which the national government alone has sovereign (ultimate) authority.
enumerated (expressed) powers
The seventeen powers granted to the national government under Article I, Section 8 of the Constitution. These powers include taxation and the regulation of commerce as well as the authority to provide for the national defense.
Article VI of the Constitution, which makes national law supreme over state law when the national government is acting within its constitutional limits.
“necessary and proper” (elastic) clause
The authority granted Congress in Article I, Section 8 of the Constitution “to make all laws which shall be necessary and proper” for the implementation of its enumerated powers.
The federal government’s constitutional authority (through the “necessary and proper” clause) to take action that is not expressly authorized by the Constitution but that supports actions that are so authorized.
The powers granted to the states under the Tenth Amendment to the Constitution.