Originally Posted by Malavita
Ironically, when Gotti became Boss, he made sure to strengthen Tommy Gambino's crew by transfering a few soldiers into his regime.

I think Gotti knew Gambino wasn't a threat to his leadership and although he wasn't a big street guy, he was well liked within the family and got some respect because of his father. Not to forget his big money operation in the Garment district. So Gotti was smart enough to keep him around

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I got the sense that Tommy was never really into Cosa Nostra. There is a quote he made on a wiretaps where he says “I never did what I wanted to do it was always for my father, for my family, etc”