I think some light moderation to actually diminish the constant personal attacks and streams of vitriol that contribute little to the conversation would actually go a long way to creating better discussions in the political subforum. If all someone is doing is constantly attacking and insulting people they disagree with in an attempt to drive them out of the conversation, while contributing absolutely nothing to the conversation themselves, I wouldn't be upset if they were moderated in some way.
I don't even know if moderation is necessary as the first step. As I said in another thread, as an experiment, we should simply cut all button ratings in GD/politics. I'd personally be fine with cutting all button ratings, forum wide, but I do think that including them in the video game subs might incentivize people to post there more.
The button system incentivizes extremism and low effort posting. It's also a major mechanism of group think enforcement via carrots on a stick (approval ratings) and sticks (disapproval ratings). Cut the button system and see how it affects the general culture of the forum. I don't think it would change things overnight. It'd probably be a gradual and slow shift, but I do think it would cut back on some of the main incentives for much of the bad behavior and group think, without having to outright censor anything.