The following article contains spoilers from "Home" from Superman: Kal-El Returns Special #1, available now from DC Comics
The ending of "Home" from Superman: Kal-El Returns Special #1 (by Alex Segura, Fico Ossio, Lee Loughridge, Dave Sharpe), the final chapter in the story about what happened following his immediate return to Earth, saw Superman transported away. This would inevitably lead to the "death" of the Justice League. Putting that aside however, there was something much more important about the timing of his disappearance: Warworld was still in Earth's orbit when Superman was taken.
This means that Warworld, and all its people, have been near Earth this entire time during the Dark Crisis. Yet, as the universe was falling apart, and the adopted home world of their liberator was being destroyed, they did nothing. The Warworlders are not powerless, they could have intervened. So why didn't they?
Superman's Warworld Was Present During Dark Crisis
In retrospect, this should have been something everyone was asking themselves. The exact timing of when the Justice League vanished and the Dark Crisis began has largely been up for debate. Now though, it has been confirmed that it all started shortly after Superman returned to Earth. The big problem with this is that the Warworld was left just sitting there that was ultimately a waste of their potential. During the Dark Crisis, the heroes of Earth were pushed to their utmost limit as an army of villains began attacking them and everything they stand for. Throughout it all, the Warworlders did nothing.
The people are Warworld are not helpless. In fact, most, if not all, are trained fighters, and a good portion of their population are Phaelosian. These are Kryptonian offshoots who have similar abilities to Superman. In fact, they are arguably stronger than the average Kryptonian because they were exposed to a white sun's radiation. They could have swept in at the eleventh hour, routing the Dark Army with ease, but instead they just sat back and watched.
Why Didn't Warworld Help Superman During Dark Crisis?
There could be a number of reasons why Warworld didn't offer assistance. One that seems likely is that the Warworlders were (in an ironic twist) done with war. They fought a long and bloody conflict for their freedom, and one could not blame them for wanting to lay down their weapons after a lifetime of fighting. Of course, there could have been other reasons, perhaps relating to their own trauma. The death of Superman would have impacted them as well. The Warworlders came to view Superman as their hero and liberator. Without him, they never would have had the courage to overthrow the line of Mongul.
He must have seemed invincible to them. Then he seemingly died just on the cusp of helping them find their own place in the universe. That would have been a devastating blow, perhaps both causing them intense grief, and also fear. They could have been held back by a period of mourning for their fallen hero, or they might have been terrified about their chances. Superman was the greatest among them. If even he fell, then what chance would they have. Then again, it is possible the writers of the series just deliberately ignored the Warworld, not wanting to give the surviving heroes an easy way out of their problems.