The Constitution mentions "Letters of Marque and Reprisal", but it nowhere suggests that the a person must ask permission to own a war ship in order to carry out such actions. That a private person might own the equivalent of a warship was a given at the time of our nation's founding.
Any limitation of the Second Amendment to what a lightly armed infantry man might carry is a recent invention. Even as recently as 1934 the Congress merely attempted to tax machine guns because it recognized that it had no authority to outlaw them.
Tell me why you think the Second Amendment says "keep and bear arms" instead of "keep and bear the battle equipment of a soldier"? Tell me how your interpretation squares with the Miller decision which suggested that general usefulness to a Militia was the criteria to use, and not whether a common soldier carried the weapon?
"Tell me how your interpretation squares with the Miller decision"
Given our current society, I would say that my position is a reasonable application of the RKBA of the second amendment.
Now, you can argue that, technically, the second amendment allows for more powerful weapons. And, technically, the first amendment allows for all speech, including profanity, libel, slander, and "fire" in a theater.
But I believe that society may place reasonable restrictions on both. I've stated my definition of reasonableness; yours is different.