I think it's interesting that you mentioned the Kennedy's. Everyone knew that Joe, Sr. was a criminal. There were rumors about his money having been made during prohibiition (maybe he ran molasses ), and his rather ruthless trading practices were well known. As a matter of fact, when he became head of the newly formed SEC, it was said that most people likened it to allowing the felons to guard the prisons. However, his quest for legitimacy by seeking the highest office in the land for one of his sons is similar to Vito and Michael's chat in the garden. Vito, too, wanted that same sort of legitimacy for his grandchildren.