That's true... but so does the presumption that the world can be divided up into races based on the superiority of certain races over other races. And that expands beyond expressing political opinions. When management is labeling your entire being and your whole family as inferior, it sucks to even be at work.

Edit: I don't mean to oversimplify, it's not just an issue of casual racism, for some things it's life and death -- when the company lobbies for loopholes in the law and then dumps toxic waste that overflows into your backyard, would a fear someone felt to avoid expressing a political view in support of that loophole override the fear someone else might have for their kids getting cancer?