Assuming the interlocutor is stupid, at any scale, 1-1 to the whole of american politics probably just highlight that you don't fully grasp their point of view, because then it wouldn't be stupid. You'd be able to explain it to them and get them to see the matter from your perspective. If you can't do that, then you don't know you're right, you might be, but there's no way for you to know, truly.

No, this is specious. I've tried to have conversations with reactionaries on topics that we both are even aligned on. It would always be crickets the moment I deviated from the reactionary talking points. The elusive point of view that is "not grasped" is merely some combination of religious fundamentalism and spiteful destruction. Which are both ultimately just rooted in stupidity.