The US is a lot more like Russia and the CCP than most like to admit, and the rest of the world needs to stop thinking Americans/America is the 'shining city on the hill'.
And well, pretending human's aren't animals with slightly better tool use and self-recognition skills one of those lies that the liberal world order/media has pushed onto a lot of the younger gens in the West. People like to pretend human's are Vulcans, when most of the world is closer to Klingons, and no amount of 'civilization' will change that.
Worthy or not, it's a slur that would only come out of the mouth of KKK-like folks in the US, and would likely result in a physical altercation that, depending on the mood of who it was said to, could escalate to lethal levels.