the guns in the hands of the people who choose to keep and bear them, is to be "well regulated."

Yes, that's the crux of the matter. Does a group of paranoiacs, afraid of the very government they claim to espouse, constitute a "well regulated" organization? Ought they to be included in the fundamental system of governmental checks and balances, or are they a threat to "well regulated" government? On the other side, as has been noted by others, are the anti-gun fanatics not just as much a threat to the Constitution? "Well," and by whom?