What are the ongoing debates among historians about Chicago Organized Crime?

According to Robert M. Lombardo, author of Organized Crime in Chicago: Beyond the Mafia, the study of crime in Chicago has long been plagued with controversies. While the media and public focused intense attention on notorious organized crime figures such as Al Capone, very few sociologists studied organized crime in a scholarly way. One of the few was John Landesco, who published Organized Crime in Chicago in 1929 (this book was reprinted in 1968). Landesco differed from most sociologists in the Chicago School of Sociology by laying blame for organized crime on the business community and the government of Chicago, and he advocated a reform of the social structure of Chicago, including services to integrate Sicilian immigrants into society, and the reform of the police department. He believed that the business, government, and social stratification of Chicago gave rise to organized crime, not immigrants themselves. 
Another debate among historians and sociologists is how to even classify organized crime. The term "organized crime" has become interchangeable with terms such as "the Mafia," "the Mob," and "Cosa Nostra," though each group has a different meaning and different membership. The study of organized crime has been muddied by public opinion and media reports on organized crime, which often give it an entirely Italian-American character. The "alien conspiracy theory," as Lombardo calls it, states that organized crime originated in the Sicilian Mafia, but other researchers, such as Lombardo, believed it developed in the United States as a response to the American social structure. The historians and sociologists who believe organized crime originated in the U.S. state that it was a vehicle of social mobility in certain communities and a means of providing social services.