Bingowings said:

There were many people back in the day who thought that Conquest Of The Planet Of The Apes (too many of thes in that title I think) was racist because it was seen to have portrayed the Watts Rioters (apparently the inspiration for much of the film) as apes (a derogatory image often used to depict people of African origin).

I havent seen that film since I was a wee lad, but if that's the case, both the Watts riots and minorities-as-apes are pretty strong imagery to use lightly.