Miklo the sicilian mafia consider the americans like cousins while the ndrine are blood related families that send their members around the world but the roots and the decision remains in Calabria. The rizzutos enemy aka the Siderno group take the name by Siderno in Calabria.
While a sicilian or a Neapolitan could decide to join the american mafia a Calabrian will prefer to ask his ndrine the ok to start a group out the Calabria.