According to Jim Kallstrom former special agent of the FBI the early 70's was the golden age of the mob, when they had the strongest grip on legitimate business in the US. The Gambinos were without a doubt the strongest family in that period, so I think we can fairly certain say that the beginning of the 70's to early 80's was their strongest period..
Then Guiliani and them FEDs had to spoil the awesome party with that damned RICO act
I think for about a 25 years period, from the late 1960s to the early 1990s, the Gambinos rivaled the Genovese in many ways. Perhaps even to the point where the Gambinos moved from being #2 to #1A. But they never supplanted the Genovese as the top family in the country, even when Gambino was the single most powerful boss. Massino was the top boss (being the only one left on the street) in the early 2000s but that didn't make the Bonannos the top family. The top family is whoever has had the most powerful and wealth as a whole. And that's always been the Genovese family.
"You keep hearing all this crap about Gotti being the boss of the bosses, but the Genovese have always been the country's most powerful family."
- Richard Ross, FBI (1990)
"I've always felt the Genovese family was the more powerful of the two. It has been able to operate in the shadows while the Gambino family grabbed the attention of law enforcement and the public."
- Ronad Goldstock, Director of New York State Organized Crime Task Force (1992)
"The Genovese family was, I think, in many ways was the most powerful family in the country in terms of it's domination and exploitation of labor unions and legitimate businesses."
- Michael Chertoff, former NY federal prosecutor (2000)
