American-style federalism is based on the new concept of sovereignty or supreme sovereignty. In the political theory of Britain and Europe, sovereignty is unitary and inseparable. However, in the imperial crisis that existed before the independence of the United States from Britain in 1776, the colonists suggested that although the British parliament controlled the overall affairs of the empire, in fact, the colonial legislature made its own laws. However, despite this, the early American government during the War of Independence still operated according to the old concept that sovereignty was indivisible.

According to the first American Constitution 1783 "Confederate Regulations", every state or former colony has supreme power; Countries only deal with national issues through "friendly alliance" relations. However, this kind of federal government is not satisfactory in practice, and even in the eyes of some people, it is dangerous. Some countries not only deprive some citizens of their freedom, but also often seek their own interests at the expense of the overall interests of the country. The general dissatisfaction with the confederate laws and regulations led 1787 to convene a constitutional conference to draft a new constitution.

The biggest feature of federalism is decentralization, and sovereignty is shared by the Federation and the States. This not only respects the long-standing tradition of American States exercising various powers independently, but also meets the requirement of expanding central power when entering the United States.