I think there’s definitely an argument to be made in that direction, but it runs into some problems. Guns were state of the art quite a while ago, and the current state of the art is just too dangerous for individual control. I don’t think many want to live next to someone who is exercising their right to grenades, NBC weapons, missiles and rockets. If we look beyond guns to the broader issue of self defense, and take that more to mean armaments, then we have to seriously entertain civilian ownership of tanks, jets, and the rest of a modern arsenal.

I’m not prepared to argue in favor of that, but without it, there is no real argument that some man-portable guns represent a credible self defense when compared to a government. If we look out another hundred years when robots are the majority combatants of developed nations, the issue becomes even more difficult to manage. The argument can still be made that a well armed populace wouldn’t be confronted by a well armed military as in the US declaring martial law and the army being turned loose. I’ve heard staunch 2nd amendment advocates point to insurgencies in everything from Vietnam to Baghdad as examples of how a relatively lightly armed populace can hold off the US. Even if we accept that st face value, the proposition certainly dies in the face of automated warfare.