Importing American media representations of black people + them not studying American history + having barely any black people in Japan leads to things like this.
Rather than "fuck you!" the response should be telling Japanese people why these sorts of things aren't okay in America and other countries. Directly. Not expecting them to research the topic on their own. It's kind of ethnocentric to expect all Japanese people to know about American racial taboos when it's not a part of their culture. Japanese people don't care nearly as much about America as Americans assume they do, so when people ask "how could Japanese people not know that this is not okay from an American perspective!?" the answer is: quite easily. They didn't even think about the implications, because they don't know the implications and don't ever have to think about them in their lives. Sort of like how most Americans don't ever really have to think about Japanese people and casually call them all pervert pedophiles because they saw an internet article about it or their older brother's friend had one of those japanimation tentacle cartoons. Or like how a young American asshole went over and videotaped the corpse of a Japanese person and put it online, despite the fact that he would never have done that if he had found an American's corpse in the forest.
We all need to work on seeing each other as real people, and not just caricatures, in order to avoid these sorts of cross-cultural outrage.
