>your offensive, inappropriate retort has absolutely no place in this discussion

I assume that means you're unaware of the historical meaning behind the quote: http://en.wikipedia.org/wiki/And_you_are_lynching_Negroes

The fallacy in question is also known as "tu quoque".

Edit: Also, it's interesting how often I point out a fallacy in someone's reasoning, only to have them say "there's no fallacy". In virtually every case, the situation was that they simply didn't see the fallacy. A better answer would be "I don't see the fallacy you're talking about."