I don't think the gov't plays favorites when it comes to organized crime. The Italian Mafia was here first, was the biggest and the most powerful. So that's where the effort was concentrated.

The Italian Mafia is losing power to the Russiand and others for more reasons than just the gov't. The Russians, the Triads and others are simply more ruthless and hungry at this point. Even without gov't interference, the Italian Mafia would still be in a state of decline at this point.