It’s so odd to see people putting words and ideas in my mouth. OTOH, I’m used to it.
No one thinks they can fight the military, no one has these bizarre fantasies. At least not among us “normal” gun nuts. I consume a fair deal of gun content on YouTube, and while I may be biased because I shy away from the right-wingers, I get not a single whiff of what you’re talking about.
Can’t find my old post in /r/liberalgunowners, but no one imagines a toe-to-toe fight. The US military, and even the cops, depend on civilian smarts, labor and supply chains. And those are easily disrupted. People point to Vietnam and Afghanistan as examples of poorly armed locals successfully fighting back. And those fights weren’t in our literal backyards among our neighbors!
But to bring it closer to home; What does this particular lib do when the local Brown Shirts come knocking to disarm me “for my own good”? That seems a very real thing to me. So do I lay down and get on the train later? Or… what?
Thought experiment; Let’s magically take every gun from every citizen excepting cops and military. How long you think until the GOP drops the hammer and goes full-on fascist? Deterrence is a thing. MAD got me through the 70s and 80s.
As to your link on the lethality of AR-15 rounds, paywalled, but I’m familiar. .223 or 5.56 rounds are tiny and hella fast. (My smart-assed take here: imgur.com/a/kolUESz.) The article’s take is for people unfamiliar with the horrific damage rounds of all sorts impart. tl;dr: Bullets don’t punch holes like an icepick. Shoot an empty vs. full can of beer with a .22, you’ll get it quick. A bullet is the response of last resort.
(And BTW, an AR-15 is illegal to hunt with in some states because the round is not lethal enough for a clean kill.)
And yes, the AR-15 is a military rifle. The title, and possibly the poster (don’t know his work), is revolting, but none the less, this is a solid history lesson. I had not thought all that through, but yes, the US civilian has always had better arms than the US military. The “military rifle/round” argument falls flat with me.
Look at it through a modern, more liberal lens and say, “I sure wish the cops could outgun us all! They’re perfectly trustworthy utilizing deadly force!”