It's hard to see Political Correctness in action when it's supporting your own political beliefs. It's easier seen from the other side. You can see in in the recent case of football player Colin Kaepernick, who has refused to stand for the national anthem. Many are condemning him, on the grounds that his speech is not politically correct.
For example, ex-teammate Alex Boone criticizes him for disrespecting the flag, because his brother has friends who died in the wars in Iraq. Others in the NFL like Burgess Owen and coach Ron Rivera have made similar statements.
If you think Kaepernick is wrong, then argue that he's wrong. Don't argue that he shouldn't speak on the grounds that he's not Politically Correct, offending veterans, or is a bad citizen.
We live in a country of freedom, where anyone is free to not stand and salute the flag or sing the anthem. So many have grievances of some sort or another that you'd think more would be availing themselves of this freedom. The problem here is not that Kaepernick does it, but that so few others do it as well. The problem here is Political Correctness.