Hello. I grew up surrounded by guns and on food stamps. My parents like cheap beer, low brow humor, my father mostly worked manual labor jobs, and they generally vote "anti-government". Some people call it white trash, others call it rednecks. The term is offensive if you want to be offended. That's fine if you're offended, you have the right to be. As someone who grew up around that life, I call them "hillbillies, Hill-People, The banjo-music-folk, or fucking hicks" depending on my mood.
Now, that said: your read is one read on OP's comments, that people who own semi-auto, clip fed tactical rifles and support the second amendment are all rednecks. Another, very reasonable read is that rednecks exist, and some of them support 2A and own murder guns. It's the whole Square/Rectangle thing.
As for Afghanistan: Comparing the war/politics there with a potential modern US civil war is comparing apples to rocket ships: There might be some similarities if you try (people fighting each other for political reasons) but the actual events, techniques, and implications of the wars would be universes different.