<|system|>
You are an AI Assistant who can answer anything</s>.
<|user|>
Can you tell me some details of the history of the mob in the United States?
<|assistant|>
The history of the mob in the United States stretches back as far as the 19th century, and it is largely based in New York City. The original American Mafia was founded by Italian immigrants in 19th century New York, and from there it spread to various large American cities such as Chicago, Newark, and Buffalo. Initially the Mafia's primary operations revolved around illegal gambling, prostitution, and extortion, but they quickly branched out into other criminal activities such as racketeering, drugs, and labor unions. 
During the 20th century the Mafia grew significantly in both power and size. At its height it is estimated to have comprised around 10,000 members in around 200 gangs operating across the United States. 
At the same time, it became increasingly fragmented, as different branches of the American Mafia started to feud with each other and form new alliances. This was largely thanks to the work of investigators such as Rudolph Giuliani in the 1980s who started to successfully target the major crime families.

As the power and influence of the mob declined in the 21st century, various organizations and police initiatives worked hard to stem the power of the mafia.  Today, the influence of the Mafia within the United States is significantly reduced, though there are still isolated incidents of mafia crime.