Seeing that my edit in The Great Diamond Authority page has been undone, I'd like to explain my point here.
In my opinion, PD's shattering isn't what started the war. A short explaination of why, is already in PD's section of the same page (which is contraddictory), but I'd like to give my reasons in depth here.
- Jasper was made halfway through the war: as shown in "Beta", Jasper was made in the Beta Kindergarten, which was made halfway through the war because Homeworld needed new soldiers. This point is reinforced by what Eyeball said in "Back to the Moon": Jasper came out of the ground with her helmet on (and flexing, apparently) and defeated 80 CGs before sundown. How could she have done that if the war hadn't started yet?
- Pink Diamond was shattered after Japer was born: why would Jasper be so in pain thinking of her diamond if she wasn't around at the time of her death and was never assigned to her? Also, Eyeball didn't object when "Jasper" (Amethyst) said that she was "around" at the time of her shattering.
Thus, by transitive property, Pink Diamond was shattered after the beginning of the war, maybe even towards the end of it.
The fact that she was shattered after the building of the Beta Kindergarten (made for the war), also confirms that she was shattered when the Rebellion had already escalated to a full war.
What do you think?