Something else that I’ve wondered is why did Vito include all his top people in the meeting with Sollozzo, but go it alone with his plan afterwards? Was Vito worried, that his top people might turn against him over the drug business? It’s possible that he eventually told the others about sending Luca on his mission, but we don’t know if he absolutely did. The meeting after Vito’s attempted hit showed that they didn’t know where Luca was or whether he was still loyal.
Good point! As we know, it was Vito's policy to give orders to subordinates one at a time, using Tom as the intermediary. That way, if anyone (even Tom) turned rat, they'd never be able to give the police another witness--a corroborating witness--who could back them up about Vito's criminal orders. Luca reported to Vito directly, not through Tom. That was probably because only Vito could control Luca, and it was probably prudent for Vito to flatter Luca with that special relationship. What's more, since Luca was Vito's one-man murder machine, a lot of those orders probably involved killing, so it was best that Tom wasn't part of the order chain. I'm
guessing that Vito figured that he might have to have either Sollozzo or Tattaglia whacked at the end of Luca's fact-finding mission, and who else but Luca would do it?
Conversely, everyone was present for the Sollozzo meeting because Vito had already made up his mind to say no. If anything, he was arming himself with plenty of witnesses who'd heard him say "no" to drugs, in case Sollozzo ever tried to implicate Vito in his scheme to save his own neck with the police. Vito may also have had everyone present because he suspected (rightly) that some of them (like Sonny and Tom) were hot to get into the drugs business--and he wanted them to know that he was against it foresquare. So, if hotheaded Sonny decided to do some drugs action on his own,he'd have Tessio, Clemenza, Tom and Fredo to remind him of his father's opposition.
