Well that's a big reason why the 90% of the Mafia's remaining membership is in the Northeast. At least 70% in NYC alone. Because there are a lot of Italians in that region. But even there, the assimilation of Italians has been going on for years now, including marriages with other ethnic groups. There are still plenty of full blooded Italians in New York but, as there are increasingly less and less of them who want to have anything to do with the Mafia, members who are only part Italian will probably become more common.