Disagreements over federalism defined politics in the early American republic, with figures such as Alexander Hamilton and Thomas Jefferson offering competing visions of how power should be divided. Following the failure of the Articles of Confederation, which had created a national government too weak to function effectively, the Constitution established a federal system with a stronger central authority while preserving the states as autonomous centers of power. It maintains this balance by specifying federal responsibilities, giving Congress the flexibility to act when necessary, and leaving most day-to-day governance to the states.
Throughout American history, federal power has expanded relative to the states, primarily through Supreme Court rulings and national responses to crises. For example, the Civil War and the Great Depression led to significant expansions of national authority. Today, federalism debates play out in clashes among federal, state, and local governments over issues like abortion and immigration.