Reading DU too often is the antithesis of the novel experience.

[muriel_volestrangler]

17. A political system can encourage entrenched positions

One thing that might help debate is going international - so that there are at least a few different entrenched political systems involved. I post occasionally at http://politicsforum.org , which is populated by people from all round the world (in English, but there are still a good amount of non-native English speakers). You'll find some real extremes there, or on other similar boards, but I think you're more likely to pick up a conversation with someone who disagrees with you on some things, but will discuss it reasonably, than on an American-only board (or one that is effectively American-only, like Discussionist). Just the effort of having to explain to, or argue with, people from different systems can help people be more open to dialogue.