Puzo was first and foremost a wonderful story-teller. In telling stories about Sicilians--both in their native land and in America--Puzo was reflecting his own observation that Sicilians, so often invaded, brutalized and downtrodden, had to be more clever and cunning than other people in order to survive. And yes, there were plenty of racist remarks and observations in the novel (and the film), but there I think Puzo was accurately reflecting the racism of Mob guys, who look down on eveyone in general, African-Americans in particular. The irony is that Italian-Americans probably have suffered more from bigotry than any other group of white Christians. Puzo noted in the novel that even Don Corleone bore stoically the mockery and bigotry he suffered in his early years, when he worked in the railroad yards.