I am black. I am sure you did not realize this when you made/laughed at/agreed with that racist remark. In the past I have attempted to alert white people to my racial identity in advance. Unfortunately, this invariably causes them to react to me as pushy, manipulative or socially inappropriate. Therefore, my policy is to assume that white people do not make these remarks, even when they believe there are not black people present, and to distribute this card when they do.
I regret any discomfort my presence is causing you, just as I am sure you regret the discomfort your racism is causing me.
Adrian Margaret Smith Piper