God I hate those words" politically incorrect"
I think you mean the historically correct Nazi flag!
That phrase is used to denounce one form of censorship by replacing it with another.
Dictators and would be dictators love to use pat little phrases like that,which usually implies that those who are considered politically incorrect should be either censored,punished or sent some where to be re-educated.
The fact that those phrases have crept into the vocabulary of every day usage by corporations,government and the educational system is very disturbing!!