There shouldn't be a line, none whatsoever, which was the intended purpose of the 2A in the first place. We all should have the opportunity to own whatever we can afford without government restriction. This man is an excellent example of what should be allowed and what I would inspire to be, just without having to jump through the bureaucratic hoops to get it!
If you can't see it's a controlling issue by the government, there is no other explanation. Even if all restrictions where lifted, there's no chance civilians would ever be able to own major weaponry that would challenge the Federal government. They just want us to be subjects, something the Founding Fathers were very experience with and wanting to avoid in the future. Unfortunately, we've slipped further down that slope over the years; and given their druthers, the Fed would have similar restrictions to civilian weaponry that exists in the UK where a pointy stick can get you in trouble!