"Africans/Blacks/Gays/Arabs/Immigrants/Trotskyists/Opponents of evil regime X are such a virtuous and naturally blessed group that they can do no wrong, and everything that they believe as a group must therefore also be correct."
They won't make that statement explicitly, but they will accuse people who point out specific cases where said group isn't virtuous or is doing something wrong of racism/sexism/homophobia/Islamophobia/victim bashing.
Yup, but that's mostly unfalsifiable; people with different values can find different things unacceptably racist/*phobic/whatever. And they aren't really hiding the fact that such accusations are just part of ideological warfare, or that they are partisan on those issues.
I have found this most wonderful (if fairly lengthy) article, and thought you would enjoy having it brought to your attention.
It is so good, I think we should include it among the references in the "Politics is the Mind Killer" wiki page. But, before that, I submit it to you, and ask you: is there anything in this article that would warrant its exclusion from this site? I mean, besides the fact that it is about politics, and written by a notorious Social-democrat (And is that in itself grounds for exclusion?).