If he doesn't like the conversation, let's encourage him to stay and provide evidence for his point so that HN doesn't become an echo chamber. I find this model very helpful: http://www.paulgraham.com/disagree.html
I've done that! I did that with Slashdot, and Reddit, and a few other places besides. You guys seem to follow me into whatever new place I end up, and start the politics conversation back up again. Why can't it be you guys who leave for once? :c