Then I remembered (way back when) I had turned 18 and was required, by law, to register for Selective Service. This made me an "able bodied American man" who could "be called up as necessary" into "military (militia) service".
No. It made you eligible to be drafted into either active duty military or military reserves.
The militia consists of all able-bodied men, women, and children who're able to bear arms. So said the Founding Fathers, including those who penned our Second Amendment, and so said the following 1982 Congressional document:
The Right to Keep and Bear Arms
REPORT
of the
SUBCOMMITTEE ON THE CONSTITUTION
of the
UNITED STATES SENATE
NINETY-SEVENTH CONGRESS
Second Session
February 1982
Printed for the use of the Committee on the Judiciary
______
U.S. GOVERNMENT PRINTING OFFICE
WASHINGTON: 1982
88-618 0
For sale by the Superintendent of Documents,
U. S. Government Printing Office
Washington, D.C. 20402
I agree with both our Founding Fathers as well as the contents of this document, which states: "...the Framers used the term "militia" to relate to every citizen capable of bearing arms, and that the Congress has established the present National Guard under its own power to raise armies, expressly stating that it was not doing so under its power to organize and arm the militia."
The reports makes another interesting observation:
"In the Militia Act of 1792, the second Congress defined "militia of the United States" to include almost every free adult male in the United States. These persons were obligated by law to possess a firearm and a minimum supply of ammunition and military equipment. This statute, incidentally, remained in effect into the early years of the present century as a legal requirement of gun ownership for most of the population of the United States. There can by little doubt from this that when the Congress and the people spoke of a "militia", they had reference to the traditional concept of the entire populace capable of bearing arms, and not to any formal group such as what is today called the National Guard. The purpose was to create an armed citizenry, which the political theorists at the time considered essential to ward off tyranny. From this militia, appropriate measures might create a "well regulated militia" of individuals trained in their duties and responsibilities as citizens and owners of firearms.
It continues:
...when Patrick Henry delivered his famed "Give me liberty or give me death" speech, he spoke in support of a proposition "that a well regulated militia, composed of gentlemen and freemen, is the natural strength and only security of a free government...." Throughout the following revolution, formal and informal units of armed citizens obstructed British communication, cut off foraging parties, and harassed the thinly stretched regular forces. When seven states adopted state "bills of rights" following the Declaration of Independence, each of those bills of rights provided either for protection of the concept of a militia or for an express right to keep and bear arms.
And concludes in the following manner:
Finally, the individual rights interpretation gives full meaning to the words chosen by the first Congress to reflect the right to keep and bear arms. The framers of the Bill of Rights consistently used the words "right of the people" to reflect individual rights — as when these words were used to recognize the "right of the people" to peaceably assemble, and the "right of the people" against unreasonable searches and seizures. They distinguished between the rights of the people and of the state in the Tenth Amendment. As discussed earlier, the "militia" itself referred to a concept of a universally armed people, not to any specifically organized unit. When the framers referred to the equivalent of our National Guard, they uniformly used the term "select militia" and distinguished this from "militia". Indeed, the debates over the Constitution constantly referred to the organized militia units as a threat to freedom comparable to that of a standing army, and stressed that such organized units did not constituted, and indeed were philosophically opposed to, the concept of a militia. That the National Guard is not the "Militia" referred to in the second amendment is even clearer today. Congress has organized the National Guard under its power to "raise and support armies" and not its power to "Provide for the organizing, arming and disciplining the Militia". 65 This Congress chose to do in the interests of organizing reserve military units which were not limited in deployment by the strictures of our power over the constitutional militia, which can be called forth only "to execute the laws of the Union, suppress insurrections and repel invasions." The modern National Guard was specifically intended to avoid status as the constitutional militia, a distinction recognized by 10 U.S.C. Sec. 311(a).
The conclusion is thus inescapable that the history, concept, and wording of the second amendment to the Constitution of the United States, as well as its interpretation by every major commentator and court in the first half century after its ratification, indicates that what is protected is an individual right of a private citizen to own and carry firearms in a peaceful manner.