In The Godfather, Sollozzo and the Tattaglia's attempt to assassinate Don Corleone. He is shot several times in the back but survives.
An hour before the assassination Sollozzo picks up Tom Hagen. He tells him that the Don had to be killed as he stood in the way of his plans. He also asks "Sonny was hot for the deal wasn't he?". This is because he spoke up at the earlier meeting between Don Corleone and Sollozzo. Sollozzo asks Tom to make the peace between Sonny and himself.
Was Sonny speaking up at the meeting a major factor in the planned assassination of Don Corleone? Would it have taken place if he didn't speak up?