But, honestly, how is the shit done in Tropic Thunder similar to Prince of Persia, or Cleopatra, or even Khan? RDJ is playing a white guy.

I don't believe that discussion and skewering and SAYING BAD THINGS ABOUT BAD THINGS is dead, and to do that, sometimes you lay down with dogs. But it doesn't mean RDJ is in blackface, so much as he's playing a character who goes into blackface—don't write it off because it's semantics. It's semantics, and it's correct and relevant. Srsly.