A piece of DC Comics history that might surprise readers is that Green Lantern policy. It's interesting when comic stories that take place in the past reveal hidden details about major events, but this revelation certainly does not make the Green Lantern Corps look good. This news was revealed in a back-up story in Superman #257 that was written by Elliot Maggin with artwork from Dick Dillin and Dick Giordano.
The destruction of Krypton is one of the most important events in the DC Comics timeline. Many characters, not just Superman, cite the tragically doomed planet as part of their origin story. Although the specific details of the event have changed over the decades, the basic foundation of what happened remains the same. Kryptonians, either through their own fault or the natural life cycle of their planet, are almost rendered extinct when the core of Krypton explodes.
As it turns out, the Guardians of the Universe were well aware of what was happening to Krypton and sent a single Green Lantern to try and halt the disaster. This Green Lantern worked tirelessly to try and save the planet, but every DC fan knows his efforts ultimately fail. The Green Lantern was worked so hard trying to save the planet that he eventually blinded himself and Krypton explodes because he can't get the materials to stabilize the planet in time.
Like Marvel's Watcher, the Guardians have rules about not interfering too much with other species. For this reason they only send a single Green Lantern to try and save the planet rather than a bunch of them or even just an extra one to lend a hand. Also, the Green Lantern even mentions how the Guardians have the ability to transport all of the Kryptonians off of the planet before it explodes, saving an entire population from extinction. They don't though, and the Guardians’ enormously underwhelming response to the crisis is shocking given the amount of people who die because of it.
Besides the fact that it's a poor protocol for the Green Lanterns not to help too much, it also doesn't make much sense. It's been established that DC's various Green Lanterns are effectively space cops, each with a sector that they patrol. But cops call for backup all the time. The Green Lantern Corps routinely works together to stop threats. It makes sense for DC to want to insert a Green Lantern into this event to add depth to the universe's history, but Superman would definitely have some hard feelings to learn that his parents might still be alive if only the Green Lanterns had planned better.
