Superman saves the planet from giant robots, magic supervillains and invading aliens on a regular basis, but he missed his opportunity to save humanity from its most deadly enemy - itself. A scene in the middle of Action Comics #1030, written by Phillip Kennedy Johnson with art by Daniel Sampere and colors by Adriano Lucas, gives readers insight into a method Superman could have used to enact real change on Earth. Unfortunately, Superman realizes his mistake all too late.
Superman's power levels are fluctuating dangerously, and all around him are worried. Batman suggests replacing Superman with Jonathan, Superman's son, on the Justice League roster until the team can figure out how to restore Clark to normal strength. For his part, Jonathan is concerned that his father just got himself involved in what will later be known as Superman's last documented appearance before his presumed death, vanishing from the history books the young hero read during his time in the future. But Lois, knowing that Superman has escaped from worse situations (even death itself) instead busies herself with her work, visiting the libraries of the bottle city of Kandor; a miniaturized city once teeming with life. But now, all the Kryptonians are gone.
Lois Lane, ever the intrepid reporter, is in the middle of writing a manuscript documenting Kryptonian culture. She marvels at the blending of artistic and scientific philosophies, observing that they no longer put disciplines like mathematics and music in separate categories. "Although most people imagine Kryptonian civilization at its zenith as far superior to Earth's... a truer statement was that it was simply older," she writes. "Krypton's Enlightenment, its Industrial Revolution, and it's wars over fossil fuels and water were all far, far behind." She then continues to write about the loss of their technology, their art, and of course the Kryptonians themselves. Superman arrives, and Lois wishes she'd had access to Kandor's libraries years ago, while Clark admits he didn't visit enough when the city was populated.
The city of Kandor is an important part of the Superman mythos. In most stories, the city was shrunk by Brainiac and is kept in the Fortress of Solitude by Superman until he finds a way to restore both the city and its populace to normal size. Lois' manuscript detailing Kryptonian scientific advances and Superman's admission of his absence from the city both point to an opportunity lost: Kandor was essentially a living library of problem-solvers. Here was a group of people who had solved their energy crises, their battles over resources. With Superman's abilities (and the technology of the DC universe as a whole), it would have been trivial to ask any one of the Kandorians to help humanity with the problems on their horizon, both in a technological and philosophical sense. Unfortunately, by the time Lois Lane identifies how similar Kandor's history is to that of Earth, the city is empty.
For all his strength, not even Superman can solve Earth's systemic issues like world hunger, poverty, sickness, deforestation and inequality - at least, not without becoming a despot. Earth's most pressing issue are no rampaging monster Superman can solve by punching it into submission, but had he been less secretive about Kandor and used his fame to build bridges between Krypton's thinkers and Earth's scientists and philosophers, he might have helped humanity anticipate and address its most ingrained issues before they cost countless lives. The tragedy of Kandor, and Lois Lane's belated realization of how much it had to offer, may haunt Superman for a very long time.