[Morrigoon]

Are you sure it's a qualification, and not merely a justification? Perhaps the bit about the militia is intended to explain WHY they cannot repeal this right.

Also bear in mind that part of the intent of maintaining a militia is that all able-bodied men should in theory be familiar/skilled in the handling of such weapons as they might be called upon to use, if ever the militias had to be called up (in other words: if we ever had to draft all our men, or all the men from a particular area, they should know what the heck they're doing, or at least we should make provisions in law that allow the highest likelihood that the militias would be able to recruit a suitable number of able-bodied men who know what the heck they're doing). The alternative being that the militias would have had to recruit a bunch of agrarian yokels, somehow procure arms for said yokels within a reasonable time frame, and then train said yokels in marksmanship from the ground up. I'm sure the idea of ringing the town bell and having all the men grab their weapons and be ready to go in a matter of minutes was far preferable.