T.Rex Arms produced this amazing 30 minute video about not just the AR-15 but rather an entire abridged history of the development of “militarize” firearms. Those who oppose civilian ownership of any weapons that may or might be used by military personnel are likely not being truthful (or perhaps are completely ignorant) regarding the history precedent of the subject. The production quality here is off the scale. A big thumbs up from 30MC (I have watched it three times). If I have convinced you to give the video a shot then please budget the time to watch it all the way through.
It just so happens that I was working on a write-up that was basically along the same lines as this video. As there is no way I could say things better I will most likely be pivoting that write-up to tackle a different angle of the argument. Stay tuned for that.