Here's my take on the differences between the Cosa Nostra and black organized crime.

The Italians were way more organized, I think we can agree with that. I believe this was due to several reasons. First, the Italians often had close knit, extended family loyalties that reached back into the old country and held tremendous weight in their community. American blacks didn't have that kind of clan organization because their families were torn apart during slavery, and black social organization was limited to about 150 years of development. Also, Italians were white and thus had more freedom to congregate and organize. Meanwhile, American society has not been kind to attempts by black Americans to congregate and organize in any significant fashion. If Black people ever did put together anything big enough to catch whitey's attention, it would invariably get suppressed.

To summarize, I think that organization is the central issue here. As far as black organizations actually battling the mafia openly, it didn't happen too much. As earlier posters said, the main conflicts took place over numbers (in the 1930s in NYC and the 40s in Chicago) and drugs (1970s in NYC, not sure about Chicago). One thing I would love to hear more about was the situation between blacks, latinos, and Mafiosos in Los Angeles during the 1970s, when the blacks and latinos experienced a huge ascendancy. Does anybody know if there was that kind of a conflict in LA in the 70s or 80s? It would be fascinating to know how the drug trade in that area first came under Latino control in the 1970s.