In response to my last item (if you haven't read it before reading this, go read it and come back), a few liberal bloggers are pointing out that foreign policy is different than domestic policy because it often involves war. Thanks for the insight. As it happens, I was aware of this fact even before writing my last item, and I didn't think it obviates the point I was making. The quote that interested me, again, was this, by Kay Steiger:
It also helps that Scott Lemieux is right and that any sort of concession to the religious right on these issues would do nothing to end culture wars but only encourage them further.
This is the sort of thing conservatives say about foreign policy all the time. It's fairly reductive. A good response might be: yes, some members of the religious right might view Democratic concessions as a sign of weakness, but perhaps others might be somewhat less inflamed by having social policy move a bit closer to their ideal. And, more importantly, some number of people in the center might be less inclined to join up with the religious right if what they saw as the more extreme positions of social liberalism were abandoned. Viewing social conservatives as an undifferentiated mass of feudal mysoginists is not the best way to understand American social policy.
Certainly, it's a way of thinking about your adversary that's at least somewhat in tension with the kind of thinking liberals prefer on foreign policy. On foreign policy, liberals like to understand that our adversaries' thinking can't simply be defined as the negation of our own values. (I agree, which is why I'm a liberal, albeit a moderate one on foreign policy.) It's fatuous to think that if we believe in freedom, then Islamic radicals must simply hate us for our freedom, or that if we believe in equal rights, then social conservatives must be motivated by a hatred for equal rights. Moreover, our adversaries are not always monolithic, and there are times when concessions can divide or isolate them from the center, not just encourage them to increase their demands.
These are the common factors I was thinking of. I don't see how the fact that foreign policy involves war and social policy does not would invalidate this point.