The militia of the United States, as defined by the U.S. Congress, has changed over time. During colonial America, all able-bodied men of a certain age range were members of the militia, depending on each colony's rule. Individual towns formed local independent militias for their own defense. The year before the US Constitution was ratified, The Federalist Papers detailed the founders' paramount vision of the militia in 1787. The new Constitution empowered Congress to "organize, arm, and discipline" this national military force, leaving significant control in the hands of each state government.