Unable to understand and/or admit that both sides can be bad. It’s ok to admit the “your team” did some nasty shit and it doesn’t in any way cancel out what the other “team” did.
Also, Winning an argument doesn’t in any way make you a winner. Actually, an argument that someone “won” often doesn’t lead to a change for the better or even make anyone convinced that your arguments were valid.
You do know that Iceland is essentially inhabited by Vikings?
DON’T POKE THE BEAR!