Glib answers just undermine your point by showing that you have no valid response.

Should the average American citizen have access to an Abrams tank?

Ignoring that, what is the likelihood that someone could own an Abrams tank? I'm guessing that there are less than a thousand people nationwide who could afford one. Would you rather have a plutocracy than a republic? Based on your laissez-faire comments, maybe yes. Even so, the US government has many more, and they have much stronger weapons on top.

Basically, I can understand your point, but the notion that you could reasonably defend yourself against the US government simply by having access to a Tommy gun is absurd.