Firstly, the implications of calling for muslims to be "terrorists" isn't as black and white as you imagine, because it all depends and what he means by terrorist (and if you read the context in which he said it, it is all the more ambiguous). I think you'd find it very hard to win a prosecutation of Mr Naik on incitement grounds.
This is why I say Naik is a deceiving bastard. This is the definition of a terrorist:
http://www.wordiq.com/definition/TerroristThis is the definition of a criminal:
http://www.wordiq.com/definition/CriminalTerrorism is a use of violence for the purpose of political, religious or ideological goal (your prophet Muhammad was a terrorist).
A criminal violates that political or moral law. Here is an article of the difference:
http://criminaljusticeonlineblog.com/archives/terrorism-criminal-behavior-vs-terrorism/Sorry, I dont know much of Nelson Mendela can't commment on him but all I can say is the people portray others as if they're the best people in the world when evidence proves contrary kinda like Mother Theresa. Many educated Indians know she didnt do shit but the world sees her as the some sort of savior, she wasnt.