Ah, yes, and liberals are so, so kind to members of their own ranks who stray from the reservation. Just ask, say, Joe Lieberman to start a very long list of liberals who’ve been treated with nothing but respectful disagreement.

There are plenty of conservatives and Republicans who have “broken ranks” in one way or another who have not been shunned, and, there are some who have been shunned — though I don’t see how such shunning is central to conservatism so much as central to politics (for good and ill). I agree with Ramesh completely, the problem with Chait’s example is that Brock isn’t a good example of anything except dislike for Brock himself, which I think is often warranted.