Mandela's many years in prison were the result of his leadership of a "terrorist" organization that killed thousands, mostly fellow blacks, frequently in horrific ways. You're right that this was not on the scale of Genghis Khan's crimes. Yasser Arafat is a better comparison.
Based on past experience in understanding other cultures as an outsider, i am pretty sure there is something else for disliking Mandela which can only be explained by a person from within who understands the different sections of the South Africa. Can someone shed light on this ? The above argument is very weak.
