Militia (United States)

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 U.S. Constitution was ratified, The Federalist Papers detailed the Founding Fathers' 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.

Today, as defined by the Militia Act of 1903, the term "militia" is used to describe two classes within the United States:

• Organized militia – consisting of the National Guard and Naval Militia.
• Unorganized militia – comprising the reserve militia: every able-bodied man of at least 17 and under 45 years of age, who are not members of the National Guard or the Naval Militia. These are militia that are under control of the State Governors.

Congress chose to organize militias for the interests of organizing reserve military units which were not limited in deployment by the strictures of its power over the constitutional militia, which can be called forth only "to execute the laws of the Union, suppress insurrections and repel invasions." Most modern organizations calling themselves militias are illegal private paramilitary organizations without the official sanctioning of a state government.