Boats and Frohickey are technically correct, but don't go there right away.
The "Militia Act of 1792" is indeed a direct ancestor of US Code, TITLE 10, Subtitle A, PART I, CHAPTER 13, Sec. 311:
http://www.geocities.com/irby.geo/fed/1792mititiaact.html
While the 1792 statute was much more detailed in terms of organization, the nature of what the "grunts" are hasn't changed at all: male citizens between 18 and 45.
Don't believe me? Check out what the US Army has to say!
Constitutional charter of the Guard
The Militia Act of 1792
The Militia Act of 1792 subsequently expanded federal policy and clarified the role of the militia. It required all able bodied men aged 18 to 45 to serve, to be armed, to be equipped at their own expense and to participate in annual musters. The 1792 act established the idea of organizing these militia forces into standard divisions, brigades, regiments, battalions and companies, as directed by the State legislatures.
Source:
http://www.arng.army.mil/history/Constitution/default.asp?ID=9
That page is VERY useful because it traces the various changes to the act since (right up to current...you can also see what was in place at the time of the Miller decision of 1937).
Sure, a lot changed, but the core concept did NOT.
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NOW, having said all that, a number of very qualified modern constitutional scholars say that the personal right to arms has been disconnected from "militia service" since 1868 and the passage of the 14th Amendment.
The best know of these are Yale professor Akhil Reed Amar (whose work has been grudgingly supported by Lawrence Tribe) and Stephen Halbrook (who first noticed all this in his 1984 work "That Every Man Be Armed" but nobody paid attention until Amar's first law review articles in the mid-90s and then his 1998 book "The Bill Of Rights").
Basically what Halbrook and Amar have noticed is that the phrase "Privileges and immunities of US citizenship" was used extensively in Dred Scott (1856) and in that decision, listed the "P&Is" as including personal arms - which supposedly blacks weren't entitled to even when free.
So by saying that blacks were citizens, and then forbidding states from "infringing on the privileges and immunities" of citizens, the writers of the 14th were specifically arming blacks against the proto-KKK of the time (which was often the same thing as the Southern state militias!). Sure enough, speeches by John Bingham and other authors of the 14th make this dead clear - they used the language of Dred Scott to specifically *overturn* Dred Scott, including overturning the part that says they can be disarmed.
(A note on Dred Scott: a lot of people misunderstand it. Basically, the court was "legally correct but morally flawed". They decided that racist laws were OK in the US because we'd had racist laws in place before the revolution, and immediately after the states passed tons of nasty racist laws often supported by people who had founded the nation. They were sadly correct and their citations of colonial/revolutionary racist laws were accurate. So despite the end of slavery and the 500,000 dead in the Civil War a decade after Dred, at war's end the Dred Scott decision was still binding. Only a constitutional amendment could fix that.)
Problem: blacks may have been citizens in 1868, but they didn't yet have the vote. They had "civil rights" but no "political rights" - much like white women of the same period. (Voting came with the 15th Amendment a few years later).
So if blacks were to be armed via the 14th, the 2nd Amendment was being transformed from it's link to the "political right" of militia service which was akin to jury duty and voting to a "purely personal right" of self defense...without necessarily destroying the militia concept, mind you.
The first effect of this argument is to show a gaping flaw in the Miller decision - which was drafted during the period when the 14A was still largely "gutted" by the courts in a series of horribly racist cases from 1872 through about 1900. Miller postulated a strong link to "militia weapons" that is meaningless if the 14A made as many changes as it seems to have.
Second, and even better, no black armed in 1868 could have expected to do so with openly carried arms. He wouldn't have lasted very long. Concealable handguns had been common at least since the 1850s and the Mormon invention of the big-bore snubbie
, plus all sorts of pocket revolvers and the like. A Carolina freeman of 1868 could have afforded one or two used 1851 Colts or some copy thereof, and chopped the barrels enough for coat pocket carry.
This is the only Constitutional argument I'm aware of that directly backs concealed carry.
