Then you'll have to explain yourself farther. I was talking about a mandatory service time (maybe 2 years?) in a militia unit just after turning 18 - for both men and women. Once you're past your mandatory service you can certainly elect to remain in the militia if you so desire, up to whatever age seemed appropriate (50?).
Ok check this out:
The "Regular" military are armed forced owned and commanded by the Federal government with the President of the United States at the top of their 'chain of command'. Please see US code Title10 for more information.
Each individual State owns their own air force
(Air National Guard), army
(Army National Guard) and if applicable, navy
(Coast Guard). These military units do not report to the President of the United States, but are commanded by the Governor. When a Guard unit activates for a deployment in support of a Federal war, such as Operation Enduring Freedom in Afghanistan, the State essentially loans out it's state-military to the Federal government.
While Federal military units are primarily composed of full-time members, Guard units are typically made of reserve components because because a given state isn't waging as much war as the Federal government. While a typical Federal military career will consist of several over-seas deployments, a Guard career will mostly consist of natural disaster response.
The above are all "
organized", a word which I put in quotations because they are legally distinguished from "
unorganized" military. Organized military have a formal command structure and an established, recognized office and headquarters...complete with official seal, mission statement, tax status, and yes even a letterhead.
A militia can be organized, and frequently was during the revolutionary war, but is typically unorganized, officially. While there is always some kind of command structure, it is not formal, recognized by the host country or otherwise ligitomit. Subordinates can not be charged with any crime for braking any evident chain of command in an unorganized militia, for example, while they can be in an organized militia or other official military.
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As this pertains to our current discussion:
In the regular military and Guard, all weapons and equipment of every kind are issued by the organization to the individual soldier. The organization retains ownership of all weapons and equipment of every kind. The individual soldier never personally owns the machine gun they carry, the armored vehicle they drive, the MRE they eat, or the shirt on their back.
In a militia, every individual soldier brings all of their own gear, and at their own expense. Each individual personally owns everything they have; because there is no institution organization to have issued them those items.
In order for a citizen to have, carry and operate a military grade assault rifle to militia duty, s/he must first personally own it. Any weapon a citizen is not allowed to personally own will not be available to a militia.
Militias are used as a Quick Reaction Force when the regular army can not engage an enemy for whatever
(typically logistical) reason. In the civil war, militias were 'called up' so as to present military resistance when the regular army could not get to a location in time or had to few numbers and needed to be reinforced temporally.