The Godfather films are full of irony. You gotta remember, by the time GFII begins, the Don has been dead for at least 7-8 years. In those years, time's have indeed changed. The family has moved out to Nevada, they own and control tons of casinos, and lets face it, Las Vegas is "Sin City." I wouldn't put it past Tom to have a mistress. Everyone speaks about how Don Vito and Tom were such noble guys. The irony of the Don's death, after all his nobility, after all his trials and tribulations to legitamize his family....he dies a monster.