Even now, the militia is defined in the U.S. Code as the "Organized militia", which is the National Guard, and the "Unorganized militia".
TITLE 10 > Subtitle A > PART I > CHAPTER 13 > Sec. 311. Sec. 311. - Militia: composition and classes
The militia of the United States consists of all able-bodied males at least 17 years of age and, except as provided in section 313 of title 32, under 45 years of age who are, or who have made a declaration of intention to become, citizens of the United States and of female citizens of the United States who are members of the National Guard.
The classes of the militia are -
the organized militia, which consists of the National Guard and the Naval Militia; and
the unorganized militia, which consists of the members of the militia who are not members of the National Guard or the Naval Militia
Actually, Sheriff Mike is wrong about this, but not by much. the Constitution was written in 1787. The first Fedgov (as we know it) started in 1789, after elections in 1788. The Bill of Rights was proposed and passed by the 1st Congress, and ratified by the states in 1791. In 1792, the Congress passed, and President Washington signed, the Militia Act. So, the good Sheriff was off a bit in his chronology - but that is all. He is dead on about everything else here. And, yes, those of us between 17 and 45 who aren't part of the National Guard ARE part of the unorganized militia.
Do you realize what this means?
The 2nd amendment actually refers to the "militia" instead of "the people,
and the militia is defined as above,
then here is the list of people prohibited from keeping and bearing arms:
any female not in the National Guard
any male under 17 or over 45.
Fortunately, the 2nd amendment protection of civil rights is NOT limited to "the militia" but applies to all "the people".
Since this right is God given, even non-citizens' rights should be protected in this regard.