On the idea that the 2nd Amendment was meant "only for a militia..."
Actually as Madison clearly stated, and it was commonly understood, that all citizens of these United States would be armed first (already,) then possibly join a militia or be appointed to one after!
Federalist #46 "Besides the advantage of being armed, which the Americans possess over the people of almost every other nation, the existence of subordinate governments, to which the people are attached, and by which the militia officers are appointed, forms a barrier against the enterprises of ambition, more insurmountable than any which a simple government of any form can admit of. Notwithstanding the military."