The other way around seems like the intuitive way to word that.
Racism is caused by ignorance is a true statement, but it's a different premise than ignorance is caused by racism. So it's not an intuitive way to word it. It's saying something different. It goes in both directions, not just one.
I agree that explicit/intentional racism is not the only form. In the pool poster thread the other day I was pretty decided that I doubt it was intentional but it still stuck out to me as yeah, that's racism. Still, going down the path of anything having to do with cultural desegregation getting labeled racism I don't think is going to help things. Like, does this Mexican-themed party have to be completely researched and indistinguishable from an actual Mexican party to be free of racism? Are they even allowed to party in a Mexican theme at all? When there's no ill-intent and there's nothing to be bothered about imo, much unlike black face, then calling "racism" feels a little extreme. Forcing people into their cultural boxes with the race card is what I see might happen.
But what if people who performed black face have no ill-intent? Like with Zwarte Piet (Black Pete). Do you think that has been perpetuated because people who celebrate in that culture hate black people? Or do you think it's because they have a homogeneous cultural system that necessarily excludes a more intimate understanding of multicultural, or in this case black, sensibilities? I think that system should be called racist whether it's malicious or not.
Basically, I think if you have party using a theme from X-race based on characteristics of X race or culture, you're using these characteristics because they are easy identifiers from what differentiates them from you. And that makes your presentation of them a caricature. This is the definition of prejudice and stereotype, isn' t it?
Honestly, I feel you. I understand what you're asking. And I wonder the same. So I don't have an answer for you. I don't know where to draw the line. Like I said, I participate. I wore a friggin taco costume at said roommate's graduation in front of her Mexican family. I have no idea if that's okay in the greater scheme of things! I only know what I believe and that it's important to be open to the idea that no matter how hard I try to not do harm, I may not always be in the right.
I feel like your definition of racism is too broad. We may need a scale of insensitivity here. Let's not equate a Mexican themed party to black face.
They are absolutely not the same. Black face has its own problematic history. That goes without saying. But there are similarities which I outlined above. My question still remains, though. In that hypothetical situation, if no one was offended by racist behavior (black face), does it make the behavior not racist?