Come on Turnbull! Vito in a small pond? The five NY familes along with the Outfit in Chicago were, for all pratical purposes, "the" MAFIA in America and still are. The MAFIA of that period was in its heyday that would last up through the 70s. Don't you remember the wedding scene where Tom tells Vito about the judges and the Senator sending their apologies for not attending, but sending gifts? How about Vito's telling Tom to "give it to a Jew Congressman in another district, not to our paisan"?

They were different dons at different times and their worlds' operated differently. Neither achieved all they wanted, but Don Vito was a player on the national scene and sought to protect his family while Michael used his family. While Vito's soul was surely corrupted, fratracide lost Michael's soul for him.