Fans have been speculating whether or not Rose Quartz actually won the war. Sure, she drove off Homeworld, but she lost all but three members of her army. Not only that, but the cluster was planted without her knowledge, and it's on a course to destroy the Earth and everything Rose worked for. Check out the theory below surrounding Jasper, Rose Quartz, and the rebellion.
Jasper - our Jasper, the one we know - was specifically chosen by Yellow Diamond to escort Peridot. After all, she’s been to Earth, she fought in the war, she would know what’s up if perchance the remnants of Rose’s army was alive. She’s a quartz, up against a quartz - if Rose was alive.
Something happen at the end of the war, something extraordinary terrible that was supposed to wipe out all the Gems on Earth. Only Rose, Pearl, and Garnet survived, saved by Rose’s shield. But Homeworld thought everyone died. Total destruction. Yellow Diamond herself most likely thought this.
5,000 years later, Peridot’s just sent to check on the final erasing of history.
After the retreat, Rose’s Rebellion was never talked about, purposefully left out of history. Peridot knew nothing, she was probably just a random Peridot given an order by her manager handed down by Yellow Diamond. It was then that she read those ‘several hundred years of reports’, which carefully omitted information about the Crystal Gems.
But the events she reported in ‘Marble Madness’, it had to have gone back to Yellow Diamond. It can’t be a coincidence that Jasper the veteran was assigned, implied personally by Yellow Diamond. But just Jasper.
Peridot never did reported the presence of Rose Quartz back then. Just a Pearl, a fusion, and a defective Amethyst. If they had found Lapis by then, Lapis’ story would have confirmed this.
So Homeworld isn’t sure whether Rose Quartz is alive or not. There might be a few Crystal Gems left running around, but Homeworld was seriouslytargeting Rose Quartz and had thought they succeeded in eliminating her? Jasper herself thought there was nothing worthy left. She didn’t believe Peridot actually needed an escort.
Peridot: The ship was destroyed.Yellow Diamond: By whom?
Yellow Diamond suspects, but there’s enough ambiguity in the reports that could mean no one important was alive. I doubt she expected Peridot to lie to her either - she’s Yellow Diamond, after all. It’s her pride again - she wants to believe that Homeworld’s last ditch effort 5000 years ago worked.
When the Cluster fails to emerge, she’s going to send several Gems this time to not just punish Peridot, but to affirm her suspicions once and for all, and if true, to utterly destroy the Crystal Gems.
I’m convinced that after the Cluster fails to emerge, it will be the equivocal action of declaring war again on Homeworld. I don’t think Yellow Diamond will just send several gems, but I’m fairly sure Yellow Diamond is going to mount an army– or perhaps just a very large weapon.
Regardless of if it is Rose Quartz or not, she knows it wasn’t just Peridot who destroyed the cluster– it was Peridot, and several other gems. These gems have proven to be a threat regardless, and I’m fairly certain that Yellow Diamond won’t be taking any more chances with this.
In fact, I have a bit of a hypothesis that Rose Quartz has used a very specific power– one Homeworld hasn’t any control over– to attain victories in the past. It’s the power of revolution, of changing minds– it’s to teach gems that they have autonomy, and that they don’t have to listen to Homeworld’s order. I’m fairly convinced that the Crystal Gems have a history of being able to convert enemies above killing them, and that’s what has made them so much of a threat, and that’s also why Homeworld purposefully and skillfully erased their deeds from history. The Diamonds desperately wants to keep their masses from finding out that there can be a life outside of the system.
I would bet that this is why there was that devastating attack that wiped out all of Rose’s apparently quite expansive army– there was some sort of spearhead in which the Crystal Gems convinced a majority of Homeworld’s army to fight for Earth, and Homeworld was outnumbered. Thus, their only option was to annihilate everything on the planet (including their lost numbers), and I’m fairly sure they considered it a very narrow victory. Because Earth was the catalyst for this strange discovery of autonomy in gems, the diamonds want to obliterate it, to ensure that this is never revisited or rediscovered, as well as to torture the gems who rebelled, making an example out of them in the process.
If it is true that revolution is what the Diamonds are the most afraid of, I really wonder what Yellow Diamond was thinking just after one of her own Peridots suddenly turned on her like that…