I'm a white guy who grew up in Detroit attending Detroit public schools. Talk about racial minorities, I was the only white kid in every class I until eighth or ninth grade. The level of tolerance of teachers and school administrators for anti-white slurs was disgusting. If racial slurs are wrong, then they are all wrong.
That being said, someone calling you names, even offensive names, doesn't warrant a violent response. It happens, but it's important to note that it's wrong when it happens. The standard should also be much higher when it comes to trained fighters losing their tempers over someone's childish antics.