Apologies if this topic has come up before (which it probably has)--I've had a look back over previous subjects but nothing especially stood out.

Going back to 1, when the Don first refuses Sollozzo and is subsequently set up for the hit.

We know the Tattaglias are behind Sollozzo, and later we learn that Barzini was too. What I've never fully understood is why it ends up as a 'Five Families War' unless Stracci and Cuneo were in on it also from the beginning (which was never specifically stated as being the case)?

My point is this: Barzini was so deep in the shadows that even the great Don Corleone didn't know he was behind it until much later. Presumably he would have figured out if Stracci and / or Cuneo were too, by that point. Moreover, Sollozzo--a man of respect, certainly, but nobody especially important within the Five Families--not only struck the first blow, he also attempted to kill a ranking Don.

I just cannot understand why Stracci and Cuneo would side with Tattaglia (surely they were also in the dark about Barzini's involvement, being themselves 'less than' the great Don Corleone?), a pimp wrapped around this Sollozzo's little finger, and also refuse to insist that Tattaglia hand over Sollozzo, as Sonny demanded.

Was Puzo suggesting that Stracci and Cuneo were with Barzini all along, uniting together to bring down the Corleones? Nothing else seems to make much sense, as to why exactly those two ended up backing the pimp and his drug-dealing friend.