Fair point, though “well regulated” in that context also means trained, practiced, knowledgeable, right? One gets lessons and instruction? The militia leaders would presumably run some background checks for their militia members? Such requirements would help the gun problem immensely. Again, I started my response by saying I wouldn’t parse words. But there we go.
Back then it did not. Not only were militia called up “cold” from the citizenry (white males with land in the right age group), there was no professional military. Generals were minted fresh from the upper class. A big problem in the Revolutionary War (and up to the early Civil War) was that newly-constituted units, from foot soldier to commander, had to learn their jobs from square one, and were quite clumsy as a team until the strict teacher of contact with the enemy inspired attention.
Training to operate a gun effectively takes time, time that is at a premium when it’s time to constitute an army. My guess is that the amendment’s intent was to at least save on some of that training. It’s quicker to build a battalion from scratch when the soldiers know the abilities and limitations of the somewhat fussy guns of the day, because they used them regularly to, say, get some squirrels for dinner.
We’ve come a long way from a loose-knit society of horse farmers and city merchants. We now have a standing army, an officer corps with a good grasp on individuals’ promotability, and a whole mess of drill, tactics, logistics etc. to teach at every level. We have ROTC and the national reserve. Warfighting has changed beyond recognition.
Russia is the current object lesson in what happens when you undertrain your established military and your conscripts.
So imo it is less about parsing words, and more about fitting the terminology to its history, both military and social.
What you describe is indispensable today. A modern military has to do it as you describe. And militia also means something quite different. Back then , I would have been but for my age. Now, hell no. I never served or trained. While I am an average shot and can tell my trigger from my sight, I know zero about tactical cooperative behavior.
I guess I’m saying that all the things you mention, every one, are normal as breathing today. But each one evolved over the last 200-odd years. Reality has outpaced the text.