The 10th Amendment of the United States Constitution encapsulates the idea of Federalism, which entails distributing authority and powers between states or provinces and the national government. The notion that local and national governments should share the responsibilities of governing is quite old, but the concept of Federalism as it influenced the Founders finds its genesis in the 17th and 18th centuries.
Taking its lesson from the overreach of the British Crown, the first government of the United States, under the Articles of Confederation ratified in 1781, sought to ensure that "Each state retains its sovereignty, freedom, and independence, and every Power, Jurisdiction, and right, which is not by this confederation expressly delegated to the United States, in Congress assembled."
While the adoption of the Constitution in 1787 was motivated to remedy some of the ills that resulted from a weak national government the Articles had created, James Madison made it clear in Federalist 45 that "The powers delegated by the proposed Constitution to the Federal Government, are few and defined. Those which are to remain in the State Governments are numerous and indefinite." The enumeration of the federal government's powers in Article I Section 8 and the adoption of the 10th Amendment were supposed to assuage the fears of the Anti-Federalists who maintained their opposition to the Constitution on the grounds that it paved the way for the centralization of power to the detriment of individual liberty.
In general, three understandings of Federalism came out of the Founding period: state-sovereignty, states' rights, and nationalism. State sovereignty means that the federal government is merely an agent of the states, while states retain final authority over all their internal matters, even if that results in states ignoring federal law. States' rights proponents argue that state and federal governments have dual sovereignty, holding power over different realms. By contrast, according to Nationalists, the federal government can exercise its delegated powers even in areas that fall within states' jurisdiction.
The differences between these understandings became relevant most visibly during the Civil War and the Great Depression, but they have been probed continually in public policy issues of all kinds, as, for instance, the host of Supreme Court cases included in this topic page reveal.
The truth is that the essential debate between the Federalists and Anti-Federalists continues to this day. Those favoring a strong federal government, argue that policy differences between the states often create obstacles to social and economic progress. Those desiring a very limited federal government observe that localization of powers is needed to effectively protect the liberties and meet the needs of a large and diverse population, and that leaving much of the governing power to individual states provides a unique opportunity for them to experiment and discover effective solutions to societal problems.
This topic page provides an in-depth look at Federalism and States' Rights, and the debates over the meaning of the 10th Amendment. It also offers information on the application of these concepts to concrete public policy issues.