The american mafia could survive only just having as a reference the Ndrangheta, which is almost impenetrable and which supplanted in power the Sicilian Mafia.
The boys of the Ndrangheta grow and are introduced through marriages between young people who are already introduced, creating some blood ties, because no one would betray, this would impact on his family, exposing it to transversal vengeances, in Calabria Ndrangheta kids grow already knowing what is their fate, they are already indoctrinated as children.
In addition, the division into local and untouchable hierarchy that undergoes continuous changes with degrees that are discovered by the police more often, making the Ndrangheta a mixture of a criminal organization and a Masonic lodge.
I heard that through history only 30 'Ndrangheta guys have become "pentiti" and only one of those was some sort of 'captain'. Considering the huge number of 'Ndrangheta connected guys in Calabria and the rest of Italy and Europe, this is really a small number. They're by far the most respected in the criminal world because they never rat and that's why they're so successfull.
Anyway, I think that such structure is impossible to implement in the USA. 'Ndrangheta prospers because its base is a rural mono-ethnic region with almost 'medieval' values when it comes to marriage, patriarchy and clan. I'm talking about rural parts of Calabria, such as the famous village of San Luca for example. 'Ndrangheta has been recognized as a supreme authority for decades, people simply don't trust the state and there's not much the government can do about it.
Urban areas of USA where American LCN exists are a completely different environment though and it's impossible to completely isolate from it and try to live by some mediterranean rural patriarchal code of honour. Things did work well for the American mafia for a certain period of time, when the Italian-Americans haven't assimilated yet and lived in their neighbourhoods where omerta existed on a certain level, but from what I read such neighbourhoods no longer exists and LCN has difficulties recruiting new members. Once the American LCN lost its base, the decline became only a matter of time.
