U.S. States

A state of the United States (a U.S. state) is any one of the fifty states (four of which officially favor the term commonwealth) which, along with the District of Columbia, form the United States of America. more...

The separate state governments and the United States federal government share sovereignty, in that an "American" is a citizen both of the federal entity and of his or her state of residence. However, state citizenship is very flexible, and no government approval is required to move between states (with the exception of convicts on parole).

The United States Constitution allocates power between the two levels of government in general terms. The idea is that by ratifying the Constitution, each state (a) transfers certain sovereign powers to the federal government, e.g., the power to create money; (b) agrees to share other powers, e.g., the power to raise a militia; and (c) exclusively retains the remainder for itself, e.g., authority to regulate the practice of law and medicine. The tasks of education, health, transportation, and other infrastructure are generally the responsibility of the states. All states transferred, shared, and kept the same powers.

Over time, the Constitution has been amended, and the interpretation and application of its provisions have changed. The general tendency has been toward centralization, with the federal government playing a much larger role than it once did. There is a continuing debate over "states' rights," which concerns the extent and nature of the powers that the states have given to the federal government.

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