re: If Sonny Corleone doesn't get whacked, does the Corleone family win the war?

Sonny was like Uther Pendragon from Excalibur. Badarse, but also a meat-headed dummy that would eventually make his own people mad enough to kill him. Used that movie's version of "The Force" to get laid by another man's wife.

Uther was a great enough warrior to be Arthur's father, but didn't deserve to be King.

Excalibur-The death of Uther Pendragon on Youtube

This scene from the beginning of Excalibur shows a glimpse of Uther's Sonny-like personality.

Merlin giving Uther the sword is similar to Vito dying, and Sonny getting reign over the family.

But Uther, like Sonny, thought with his little head.

Not deserving of being King, or head of the family.