Shared sovereignty

Federalism in the United States is the constitutional relationship between U.S. state governments and the national government of the United States. Since the founding of the country, and particularly with the end of the American Civil War, power shifted away from the states and towards the national government. The progression of federalism includes dual, state-centered, and new federalism.

Federalism was a political solution for the problems with the Articles of Confederation which gave little practical authority to the federal government. For example, the Articles allowed the Continental Congress the power to sign treaties and declare war, but it could not raise taxes to pay for an army and all major decisions required a unanimous vote.

The movement was greatly strengthened by the reaction to Shays' Rebellion of 1786–1787, which was an armed uprising of yeoman farmers in western Massachusetts. The rebellion was fueled by a poor economy that was created, in part, by the inability of the federal government to deal effectively with the debt from the American Revolutionary War. Moreover, the federal government had proven incapable of raising an army to quell the rebellion, so that Massachusetts had been forced to raise its own.

In 1787, fifty-five delegates met at a Constitutional convention in Philadelphia and generated ideas of a bicameral legislature (United States Congress), balanced representation of small and large states (Great Compromise), and checks and balances. James Madison stated in a long pre-convention memorandum to delegates that because "one could hardly expect the state legislatures to take enlightened views on national affairs", stronger central government was necessary. This convention almost immediately dropped its original mandate and instead set about constructing a new Constitution of the United States. Once the convention concluded and released the Constitution for public consumption, the Federalist movement became focused on getting the Constitution ratified.

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