American LCN mafiosos most definitely have the "live for today" mentality, that's their most common characteristic IMO. In their mind they hope they will just keep on doing what they do and stay alive/out of prison, but subconsciously they know they can end up badly any day, particularly now when many of them spend decades in prisons. They're hedonists with no real work ethic, gamblers of sort.

One can mention greed and sociopathy as their characteristics, but there are different types of greed and sociopathic behaviour, it's too general.

I'm sure they feel some sort of isolation from the rest of society because they don't follow normal social rules/laws and live a different lifestyle. I think their sociopathy is in many ways related to this feeling. Most of them probably aren't born sociopaths but end up like this because of this particular subculture they were raised in. I also think some sort of loyalty exists precisely becuase of that (they sense that they and their friends/other crew members are different from the rest of society and have no value in this society outside of the criminal organization they're in), they do have a sense of comradery, this was also confirmed by Michael Franzese. The families wouldn't survive for a century if there wasn't some sort of loyalty.