The way this sounds is that you are more concerned about politics as in people who take party positions and may feel excluded as a group when the majority of the community takes a different position. This is a slightly different issue i.e. party politics, and I think it is fine/a good thing, but it is also important to distinguish the two. This should essentially be under the same umbrella as personal attacks, as they are essentially the same thing.
I'd rather see HN go politics-free forever. Political discussions do not enjoy the same level of objectivity that technical and business discussions do. Frankly, it may be impossible to expect objectivity within political discussion because our political feelings are so deeply-held and tied to our individual upbringings, culture, and locale.
Unless HN can figure out how to give fair treatment to minority opinions, it's best to exclude these discussions entirely.
You see this kind of problem on debates about climate change. Once people learn about environment and ecology they tend to assume that humans have an unavoidable impact on the planet. Climate change "deniers" simply have a different intuition. All the science in the world is not going to change that. Which is why it is political, and not objective.
Really the entire point of politics is to debate things that lack definitive truth. Of course that is probably true of anything that is discussed on a forum to a lesser or greater extent. Otherwise the answer would already be on Wikipedia.
But then, I guess, that person has every right to conflate moral and legal rights ... so sue me? :)