Another reason the 2A is a pertinent today as 200 years ago.

Cross-polination of equipment, bullets, techniques, etc. between the military and civilian shooters has become a force multiplier! I don't think this is getting as much press as it deserves. We should do more along the lines of this post and article to get out the message!

Which war, or police action, are you refering to? Prior to WWII there was a significant amount of civilian mfg small arms in most of the conflicts. I am unsure of the support for the banana republics, and the Spanish American outside the Caribbean.

WWII, as far as I know IBM is not, and never was, a gov't arsenal though they made their share of rifles.

Korea, you are likely correct, though this was fought with many weapons originally made for WWII.

Vietnam, weren't the Leatherwood scopes of civilian mfg? Also, I probably ought to look over Hathcock's book again, but I seem to recall mention of the use of civilian rifles for sniping, though I could me mistaken.

...John George ( Americal Division, Guadalcanal, WWII ) carried a model 70, then an M1 carbine, all 6 million of which were produced in civilian shops...Winchester, Inland ( GM ) , IBM, etc.
..Machine guns were also made by private contractors; Buffalo arms, Border cities, Ramo, Colt, Savage and others. H&R made Garands, Colt made the AR-15 and M16, Auto Ordnace, Guide Lamp division of GM, Standard of Port Clinton, Ohio, all made arms for the Goobermint. Hathcock carried a Model 70 Winchester with a Redfield scope.
...I think you are mistaken to say that " everyone carried government-designed rifles made in government arsenals ". Not true in any of our wars.