Any interpretation of the Second Amendment can only be viewed in the historical context of its time. The first sentence of the Constitution refers to the people of the United States. Isn't it logical that the Founding Fathers were referring to state militias and only state militias? It was adopted in reference to state militias. Against whom? Against common enemies. Who were they at the time? Indians who had been "relieved" of their lands against their will, and were fighting from time to time to get it back. Because states couldn't afford to individually support standing enemies, they did the next best thing . . . they gave individuals the right to bear arms when called upon by the state. Against unknown foreign powers . . . i.e., other "common enemies." The phrase . . . "the right of the people to bear arms shall not be infringed" means just that, but it applies only to a common enemy.
That's where the NRA and its supporters get off the track. As deadly, as despicable, as cowardly as a handgun-carrying individual may be, he is not a common enemy of the people. He is not attempting the overthrow of an entire community, state or nation.