Skeptics are generally united when it comes to applying critical thinking to questions about physical reality. Ask a group of skeptics about ESP, dowsing, or chi, and you'll typically find that they all agree that there is no plausible scientific explanation, and no reasonable evidence, to support the claims made about these subjects. Even when it comes to religion, any dispute among skeptics stems mainly from whether or not science can be used to investigate claims about gods. When it comes to political, economic, and social issues, however, skeptics are all over the map.
That's understandable, since science cannot resolve such issues. What I find disturbing, however, is that some of us seem to discard our skepticism completely when it comes to such issues. I've seen this, for example, in the JREF Forums and in reactions to Michael Shermer's blog posts on Libertarianism. Whether it's economic inequality, nationalized health care, the pros and cons of corporations, or the merits (or demerits) of the U.S. government, rational debate flies out the window and logical fallacies and cognitive biases take over.
Such issues are generally about value judgments — opinions about what is right and wrong, or what is better or worse for society — but that doesn't mean that you should avoid looking at those issues skeptically. This is hard, though. The tools and methods of politics are geared towards evoking emotional responses: good storytelling, rhetoric to distill complicated issues into sound bites and catchphrases, labels to group people conveniently into easily digestible categories. You're supposed to rally around a particular issue or candidate, take sides, and not think too much about it. Politicians and leaders of social movements need ardent followers, not provisional supporters who might depart if the evidence draws them elsewhere.
Critical analysis usually isn't part of the picture, at least in mass communication. The think tanks that do generate such analyses are funded by groups with particular interests, and that bias shows in their work. Statistics are chosen, or perhaps manipulated, to support a particular view. Polls are constructed with a bias towards getting the desired result. And the issues are usually large enough and complex enough that it's practically impossible for the ordinary citizen to gather objective evidence (if there is any) on the subject at hand.
Then there's the interplay between politics and morality. We want to elect people with good characters. We want to feel good about our decisions on particular social issues. Religious leaders weigh in on particular issues or candidates to influence their followers. Adherents to particular political views feel themselves to be morally right, with their opponents thus becoming evil.
All of this adds up to a hazardous obstacle course for a skeptic to navigate. It's a system that encourages the same kind of uncritical, emotionally-based behavior that we see so often in supporters of pseudoscience, alternative medicine, cryptozoology, etc., for which we can rely on science to provide answers. However, that doesn't mean that we should abandon skepticism when looking into political, social, and economic issues. It's disappointing to see that many of us do.