I think this reader’s got it pretty much exactly right. Conservatives argue all of the time about first principles. As a few serious liberals have recently noted , liberals spend most of their time arguing about strategy and “framing” while conservatives often have knock-down drag-outs about first principles and philosophy. The liberals (and some conservatives) look at these arguments as a sign of internal tensions when they’re really signs of internal health. Anyway, from a reader:

Jonah,
Your remarks on the conservative crack-up were right on (Andrew Sullivan’s banging the drum now, too, I see). The thing that kills me about such perennial reports is that they’re usually sparked by a phenomenon that the left doesn’t quite seem to recognize — honest disagreements between people arguing in good faith.
While internal debate and disagreement can, of course, be a bad thing, it’s more usually a sign of good health. It’s when such debate/disagreement stops when you should worry (e.g. today’s liberals). I am an atheist, libertarian philosophy professor who disagrees with many of the conclusions of cultural conservatives — but I appreciate the fact that conservatives still feel the need to support their conclusions with reasons and the fact that a good opposing argument generally receives a respectful hearing (Exhibit A: The Corner posts on Terry Schiavo over the past week or so).
The same just cannot be said for the left today (Exhibit B: Larry Summers). Disagree with them and you’re a heretic.
Keep up the good work and don’t print my name (I’m trying to get a job
in academia).