AITA for calling my SIL a racist and telling her to go back to her hole?

I am Asian, so is my wife. My brother is never a racist person and it is so bizarre to hear that he dated a racist. We were all shocked when we learned that his girlfriend is. I never would have imagined this from him because he always stood up for people of color growing up, went to black lives matter protests when it happened etc.<br><br>Anyway, they got married. We used to regularly go to their condo for potluck. Initially, we never knew she was racist. We were polite and courteous. We brought our dish and shared it, helped with cleaning, etc. The issue began when my wife brought kimchi. My wife is a korean-american. She grew up in korea up to age 6 then her family immigrated to the US. Kimchi is a staple korean dish. Her mom often made kimchi at home. She brought kimchi to the potluck at my brother and SIL's house. That was when the issue began. My BIL and SIL did not appreciate kimchi. They said it smelled bad. My wife was like "OK, sorry". We then stored it inside the refrigerator.<br><br>The following week, we went back and she accused us of ruining her refrigerator because of the kimchi. It was not the case because my wife and I helped clean and took the kimchi back home. We took it home after dinner. The issue got bigger and my BIL said we were not welcome anymore because my wife ruined their potluck and fridge (we did not). I then told my brother we are never going back there ever. They are not welcomed in our house either. My brother said it was just a misunderstanding and he will teach his wife to be more accepting.<br><br>We did not speak to them for a month. One day, they came to our house. My brother said his wife agreed to be more accepting and would never say anything racist again. We were polite. My BIL and SIL saw our kitchen utensils and cookware. Our cookware was korean and chinese cookware. My wife said it was given by her parents. My SIL said korean people are poor and dirty. My wife asked her to leave. My BIL scolded his wife. He said she was not supposed to say that. She argued back. I had enough and told her to go back to her hole. This caused a massive argument between us. My brother said we should be understanding and give his wife another chance. I told him off. My BIL is not speaking to me now and said I am the asshole.<br><br>Edit: I told my wife about this post. She made a throwaway account and wrote her side of the story in the comment section.