[Roger Slater]

I'm still having a lot of trouble understanding what the concept of "PC" is adding to the mix, John. If your point is that history gives us many examples of foolish notions being widely believed on scant evidence, or in the face of contrary evidence, I don't think anyone would disagree with you. But I don't get the feeling that you would use the term "PC" to describe this phenomenon in all its incarnations. Unless I am mistaken, you are reserving this term of opprobrium for just some of the examples history provides of foolish notions that were widely believed, which is how most people use the term, but I have yet to discern a principle beyond that of left versus right, with wrongheaded leftish ideas alone being considered PC in the negative sense of the word.

In the run-up to the Iraq War, most people in America were convinced that Iraq had WMD, though it turned out not to be true. But I don't think anyone looks back and says it was "PC" to think that Iraq had WMD. No, it wasn't "PC" -- the right wing believed it, too, which means it was not political correctness but somehow true even though it was actually false (as Steve Colbert put it, it may not have been literally true, but it was truthy). The small minority of left wing voices who expressed doubt about the WMD, however, were accused of expressing left-wing PC notions based on the presumption that left wingers are too soft and naive to face up to the fact that Saddam was evil and dangerous.

My point, in a nutshell, is that PC is not a genuine concept but a propaganda term scornfully uttered by right wingers to dismiss what they would have you believe is the zany, knee-jerk liberalism of those with whom they disagree.