Any way you cut it, the point was to have an armed citizenry capable of defending the country, and the 2nd was plainly defined in that context, so it makes perfect sense that the minimum requirement for bearing arms is being able to do so effectively: so where’s the training? Where’s the free gun after you prove yourself capable enough to be part of the national defense?
As it turns out, we have all that, it’s called the U.S. Military, an all volunteer force for the defence of the nation. (They don’t let you keep your gun anymore).
Want to do it part time, on an on-call basis? National Guard.
Id love it if we moved to the swiss model of mandatory training for everyone when they’re old enough, issuing them a firearm, and telling them to stay trained just in case, that would be awesome. Instead we have “buy it at Walmart, figure it out”, and zero part of that is run well.