There is evidence from correspondences of the time that the term "well regulated" as used in colonial times meant "properly adjusted/operating properly." So it could be substituted...A properly operating militia being necessary to the security of a free state, the right of the people to keep and bear Arms, shall not be infringed. In other words, the RKBA was already in place, and the militia would profit from this by government not infringing on the RKBA in any way. Hence the militia would be well regulated and ready for action because it would have arms available at a moment's notice.
When you think about it, there weren't government regulations on everything like there are nowadays. When people said regulation, they were referring to the degree of efficient functionality of something. For example, the clock is well regulated and keeps good time. I don't have to regulate (adjust) it often. [ Regulator clocks] Or, the speech that fellow made was a well regulated one. He was very articulate. If a rifle was well regulated, that meant it was a top notch rifle. Not that it was registered and licensed and inspected.
The idea of government control and regulation is a modern one, and we see the term "regulation" differently. A common error is we try to evaluate meanings using modern definitions instead of the language of the time. History is re-written/re-interpreted because we tend to judge the past by today's standards. In this case we interpret an archaic term by today's meaning. I believe the militia clause of the Second is a subordinate clause and is placed there as an example of the importance of an already existing right.
The militia clause could have been left completely out and not changed the meaning of the Second Amendment. A standing army would have been well regulated in the modern sense. The founders didn't trust a standing army at the time. Seems like the more "regulated" a militia would be, in the modern sense, the closer to a standing army it would become. This is opposite to what the founders were trying to achieve. The Third Amendment to the U.S. Constitution provides that “no Soldier shall, in time of peace be quartered in any house, without the consent of the Owner, nor in time of war, but in a manner to be prescribed by law.”
Les