"I seem to recall that the Founders had private citizens with their own battleships and artillery - hence the "letters of marque" in the Constitution.
'Twould seem to indicate that "arms" meant more than just hand weapons."
Indeed. Arms are arms; each and every of the terrible implements of war, from Liberator pistols to MIRV mounted hydrogen bombs.
It's awfully generous of you people to say 'oh sure, small arms, because that's what I have'. Because of course small arms are sooo vital to war.
Even at the time of the Revolution small arms were secondary pieces, which while necessary, were not the deciding factor in battles. Who has more maneuverability, and who has more field pieces (not just blackpowder cannons today- aircraft and WMD also are in the mix); these are what determine the outcome of a battle.
Arms means ARMS. Artillery, and counter-artillery. Tanks, and anti-tank weapons. Warplanes, and anti-aircraft weapons. Warships, and anti-warship missiles. Atomic weaponry, and their respective countermeasures.
Small arms are nice, and cheap, and fun, and flexible. But they are not 'terrible implements of war'. They alone will not win a battle against a trained military.
It was the intention of the founders that Americans be not only belligerent and suspicious of government, but at least as well armed, hopefully better on a collective basis.
Remember, nuclear weapons are a massively expensive, incredibly complex, and insanely dangerous weapons system, yet we seem to decide that nation states, as unpredictable and pathological as nation states always are, are the only entities 'responsible' enough to own these items.
Nation states are only beholden to the will of others by means of threat-of-force- the balance of power. That balance has shifted completely in favor of the government vs. the citizen since WWII.
This is not exactly a recipe for happy things.
Yes, individuals or corporate entities should be able to own nukes. These weapons are too expensive and complex to be used in an act of passion or eccentricity- rather they are the trump card of a responsible, pragmatic citizenry against the ultimate recourse of their government.
The founders didn't promise us complete safety; only the means to secure our liberty.