"Why do you need an AR15?"

[stanc]

Madison just wrote up a set of principles ― of truisms ― in which everybody believed, and the Congress duly passed it as the Bill of Rights. Two of these truisms that got cobbled into one article were: that there is a natural right to be armed; and that militias are a good thing.

Aside from the very dubious claim that said principles are "truisms," the two principles noted were put together into the same amendment because:

1. For militias to require individual members to have their own weapons, the individual members must be able to lawfully possess and carry their personal weapons.
2. The 2nd Amendment was clearly based on the Virginia version (written by Mason), which only addressed keeping and bearing arms for collective defense of the state, not self defense of the individual.

Note the significant difference between the RKBA of Vermont versus Virginia:

Virginia (1776) "...a well regulated militia, composed of the body of the people, trained to arms, is the proper, natural, and safe defence of a free state..."
Vermont (1777) "...the people have a right to bear arms for the defence of themselves and the State..."

Like the 2nd Amendment, the Virginia RKBA is directly linked to arming the militia, for defense of the state, whereas Vermont's RKBA is independent of arming the militia.