It seems that "political correctness" is only applied to liberal causes. Conservatives have their own politically sacred issues, yet there is no pejorative use

It seems that "political correctness" is only applied to liberal causes. Conservatives have their own politically sacred issues, yet there is no pejorative use of "PC" about these issues. Why is that? For example, I find flag fetishism and reciting the pledge of allegiance to be creepy. Wearing flag lapel pins is an effortless show of patriotism. Ascribing heroism to every member of the US armed forces is ridiculous. It would be political suicide for liberal politicians to express such opinions, but the reverse is certainly not true -- conservatives get bonus points from their base for dismissing liberal causes as being PC posturing.