Originally posted by Mickey:
...I was thinking about how Sollozzo and Bruno Tattaglia knew not to trust Luca Brasi when he comes to talk to them, and they end up killing them. My theory is that Barzini had a hand in that, too. Notice how Barzini is at Connie's wedding at the beginning of the film. I bet he saw Luca there and realized ...
First of all, one must assume that ALL the Family Heads would have been invited to Connie's wedding. And even if Barzini had been the only one in attendance, he would not have had to 'see' Luca there in order to know how loyal he was to Vito. Luca had been at Vito's side for many years prior to this day and I'm sure that all the Families and their leaders were well aware of the relationship.
Second...once Vito utters his famous line, "...it was Barzini all along...", we know right there Barzini was behind everything from the beginning. Sollozzo (who was backed by Tattaglia who was backed by Barzini); the killing of Luca; the assasination attempt on Vito's; the attempt on Michael's life which resulted in Appolonia's death; the killing of Sonny.
Vito is telling us in that car that Barzini not only had a hand in it, but masterminded all of it from Day One.
Really...the only thing Barzini EVER did wrong was to underestimate Michael Corleone.
Apple