Well, you're on to somewhat of a point. The 2nd Amendment was originally written so that citizens can have the very weapons of war that the military had. Privately funded militias owned cannons, and outfitted warships, for example, in the colonial and early Republic. Over time, between the NFA in 1934 and the 1986 restriction on machine guns, this is no longer the case.

The 2008 Heller decision says that the Second Amendment means that citizens have a right to small arms, handguns specifically, but not the same weapons of war as the military.

Personal firearms were the great equalizer in the past 500 or so years. They ended the mounted knight as the most powerful enforcer of state rule, and made, even more than the crossbow or longbow, the peasant as powerful as the lord on the battlefield. We are coming rapidly to the end of that era as body armor improves and it will end pretty much when drone strikes are the metaphorical equivalent to the mounted knight in armor. You can have your guns, but they can't help you much when the drones show up.

So, when drones technology advances enough, and with the restriction of armor piercing rounds, and police forces pretty much all having APCs for their swat teams, we are coming to an end of the era. It might take awhile though, as there is always a push/pull, and people will come up with signal jammers, for example, for drones.