My chat with "Don Peppino" on the forum has led me to question what Italian organized crime group formed the most powerful faction and mob contingent in America?

Since they first arrived in the U.S. back in the early 1900s, what segment of the Italian underworld made up the most powerful faction? Was it the Napolitani, the Calabrese, or the Sicilians? And of the Sicilians per se, what section of Sicily produced the largest (and for that matter, the strongest) clan?

Was it those from Castellammare del Golfo, or from Agrigento, or Palermo, Corleone, etc?

I am curious for the answer and seek your input. I think it is an interesting question.