Sincerity and respect for a person's race does not take a backseat just because someone made racist remarks to someone else. I've been the victim of racist remarks and I'm white, that doesn't make it okay for me to refer to the other person by their race. In fact, it makes it WORSE.
Being tolerant of ANYONE using racism for ANY reason is not okay.
EDIT: The more I read your comment, the more it looks like you support racism as a means of retaliation to racism. This is why racism still (and always) exists.