Once you get past the preamble, the US Constitution is a very businesslike document. There are no comments, parenthetical asides, vision statements, explanations or justifications in its following text.

That means that the RKBA as expressed in the Constitution must have some link (unspecified) to the militia, to give the first part of the second amendment meaning. Had the founders intended just “The right of the people to keep and bear Arms shall not be infringed”, that is what they would have written. They did not do that, so anyone who takes the text of the Constitution seriously is stuck with the militia.

That’s a difficult problem, since the militia as understood by the founders is a legal fossil with practically zero real world relevance today.

The Heller court simply said to hell with the militia language in the second amendment. That might be a rational response to having an enumerated right tied to a legal fossil, but conservatives really shouldn’t claim that Roe v Wade is judicial activism and Heller is not.

Taking unenumerated rights seriously enough to decide a hotly contested issue is a bold act of judicial interpretation, but it pales in comparison to simply ignoring inconvenient text of the Constitution itself.