The original meaning of "well-regulated" results today in someone being a soldier in the "regular Army" or "a regular" as distinct from a "reservist".
Some people just don't care what Heller says. They have heard about and picture "regulators" (and obey them every day) to the point they are confused about the meaning, and correcting them seems to set them back a little, in my experience. It also opens the door to explain "arms", "keep" and "bear", if their attention span is long enough.
The right is individual, but the militia is composed of individuals acting in concert.
How do they do that effectively if they don't have their own arms and resources to practice? Which idea tends to knock down the idea that the state should have custody of arms owned by individuals, or an expansive right to seize them.
Loyalty to petrified opinions never yet broke a chain or freed a human soul in this world — and never will.
— Mark Twain