It isn't about disagreeing with you, though I understand why it seems that way. It's about respecting the intent of the site.
Sometimes when users feel outnumbered by others with opposing views, they go on tilt, posting too many inflammatory comments in quick succession. Too many, because nobody can produce dozens of comments on end while keeping them all substantive. And inflammatory, because the sense of being surrounded by enemies leads one to cut corners in civility and consideration. (It feels like self-defense: they're the ones ganging up on me, it's only natural to react a little strongly, etc.) Such comments never remain unanswered, and so we get flames all over the place. This amounts to unpremeditated trolling.
Often the accounts that do this are single-purpose political accounts or throwaways, and those are pretty easy to ban, but sometimes they're good HN users, and it doesn't feel right to ban them, though I don't know what else to do besides ask them to stop.
If I say you can't scatter cigarette ash in a high-risk forest fire zone, that isn't because of prejudice against smokers. Yours isn't the only account that's been overdoing the political vitriol, but we haven't seen any other doing it so much. That may be because we don't see everything.
