Did I miss a memo?

When did it become OK to perform in white face.  Recently we've had White Chicks hit the big sceen as well as Jamie Foxx on the Espy awards portray "stereo typical" whites.  The Waynes brothers doing the rich white valley girl thing, and Foxx the trailer trash mullet hair cut hick.  Maybe a studio should get Jamie Kennedy to do "Malibu's Most Wanted 2" in black face.  You know to give it more street cred.  Wouldn't it be great if Eminem, wore black face and replaced P. Diddy in Raisin in the Sun.  That be something right?  It doesn't sit well with me that in this supposed age of enlightenment and political correctness that nothing has been said.  Black face is offensive for a laundry list of reasons, but white face is just good old fashion fun.  What happened to "do on to others, what you would want done to you?"  I would say a majority of Americans, and a significant majority of Black America find black face offensive.  Yet it seems that we (America) readily accept white face performances.  I found this posting by Bryan Thomas, and I believe his feelings on black face are held by the majority. 
When I was young and fat, I hated being called fat.  It hurt my feelings, and in many cases ruined my day.  As a result, I would never call anyone fat.  I knew what those words meant to me and I didn't want to put that on anyone else.  Aren't black actors performing in white face doing the same thing?  Maybe black face doesn't mean anything to those actors?  I dont know, but it still doesn't make it right.  Maybe this is a super simplified example, but I think it gets the point across.  Call me what you like, I think it's just wrong.