I´ve just looked up the wording the Second Amendment. It seems to me that, rephrased in modern terms, it goes like this:
"Since a well-regulated militia is necessary for the security of a free State, the citizens must not be prevented from owning small arms."
This poses several issues to me:
First, as it says "security of a free State", how does anyone get the idea that this is about people "protecting" themselves from their government, or protecting themselves from criminal? It seems clear enough that this is about defending the US against invaders.
Second, what is this "well-regulated militia"? In context with the first point, this could currently mean either the US Army or the National Guard.
Third, is private gun ownership actually necessary for the "security of a free State"? Wars are not won with pistols and hunting rifles, they are won with tanks, bombers and cruise missiles.
Fourth, assuming either that there is no well-regulated milita, or that it is not necessary for this militia for people to own small arms, or that this militia is not necessary for the security of a free State - would this mean that private gun ownership could now be prohibited?