"Guns are necessary in case we want to turn the US into an impoverished patchwork of warlords" is a hell of a take.
It wouldn’t work in the US anyway. The gloves would come off in a long running civil war as they always do and there would be collective punishment, population resettlement and other war crimes. The US is as likely to follow international law in a war it genuinely feels is an existential threat as anyone else, not at all.
Every argument the "Guns will protect us from the government" crowd claims was already proven false over 100 years ago, and that was when the average citizen was still on equal footing in terms of firepower.
There's also the fact that in the past 120 years, there has not been a concerted effort to "Rise up" despite many actual atrocities. So, gun owners, what would it take for you to attempt to march on Washington with your arms readied? The only time it ever happened was because people were denied the "right" to own other human beings. What is finally the breaking point that gets people willing to die against the might of the war machine?
Police chiefs. Mayors. Governors. District attorneys. Tax collectors. Etc.... You don't need tanks and aircraft to render these people incapable of performing their functions. Small arms (and maybe some improvised explosives) are sufficient. That's the true leverage and power of an armed citizenry backed by a supportive population. Afghanistan has repeatedly (and continues) to prove this.