A look back to 10 years ago, when the romance between Superman and Wonder Woman turned DC's New 52 upside down
Let's go back ten years to August 2012 for Justice League #12 by Geoff Johns, Jim Lee, Scott Williams (and a bunch of other inkers), Alex Sinclair and Pat Brosseau, where Superman and Wonder Woman started a romance.
WHAT WAS THE STATE OF SUPERMAN AND WONDER WOMAN'S RELATIONSHIP HEADING INTO THE NEW 52?
Due to DC Comics compartmentalized nature, with the editor of each group of titles closely guarding their characters as though they were individual editorial fiefdoms, Wonder Woman and Superman rarely spent time together for their first twenty years of existence. In fact, most of their interactions were as occasional teammates in the Justice Society of America during the 1940s. It was not until the Justice League of America was formed in the early 1960s that the two shared the spotlight regularly, and even then, Justice League of America was not a place where anything notable would happen, characterization-wise, for any of the star characters, with any developments of weight being reserved for their own titles.
By the end of the 1960s, however, DC was going through a change in how it handled its marquee players. The success of Marvel Comics and its heavily inter-related continuity led to DC adapting a similar approach with its own storytelling. As Marvel fed into fan debates like, "Who is stronger, Hulk or Thing? How about Hulk or Thor?" by addressing them in the actual comics, similar ideas DC readers likely had, like, say, "Why doesn't Superman date Wonder Woman?" were starting to be addressed as well. So there were a few stories in the late 1960s through the early 1980s that teased Superman and Wonder Woman dating, but it never actually happened.
After Crisis on Infinite Earths rebooted DC continuity, and Wonder Woman was now a NEW superhero, she and Superman had some outright flirting, including sharing a momentous kiss in Action Comics #600 (by John Byrne and George Perez)...
Even after Superman married Lois Lane, there were some interesting interactions with Wonder Woman, like Action Comics #761 (by Joe Kelly, German Garcia, Joe Rubinstein and Glenn Whitmore), where the two heroes were called upon to save the Norse gods. They travel to a magical word where they fight in a war that goes on for hundreds of years while only a short amount of time passed on Earth. The magic keeps Superman and Wonder Woman from aging much, as well. During their time together, Kelly shows the two heroes growing closer and closer as the years go by. Where once they slept far from each other in their camp, eventually they are sleeping in each other's arms. On the eve of their final battle, Wonder Woman effectively propositions Superman. He turns her down, but boy, is he tempted.
But then the New 52 happened, and Superman's marriage to Lois Lane was erased in the continuity reboot. DC was now free to do anything it wanted, but they honestly kept things pretty much the same as the old continuity, except for a few changes here and there. One of the moments, though, when they really tried to shake things up was in DC's flagship title, Justice League, where Geoff Johns and Jim Lee made Cyborg a founding member of the team instead of the Martian Manhunter, and a year into the series, they also made another major change with regards to Superman and Wonder Woman.
HOW DID SUPERMAN AND WONDER WOMAN GET TOGETHER?
In Jim Lee's final arc on the series, "The Villain's Journey," the writer who named the Justice League in the first arc is now trying to tear them apart, because he blames them for the deaths of his family (they inhaled some Apokoliptian ash from the fight that the League kicked up during its fight against Darkseid in the first arc of the series, set five years earlier). He turns the media against the team and in the end, Green Lantern (who very publicly fought against Wonder Woman earlier in the story when she threatened to kill the villain for hurting Steve Trevor, the League's ARGUS liaison) quit the team, so to draw foucs off of the fact that one of the Leaguers attacked each other.
Everyone's really down, and Trevor will no longer be the team liaison, and Superman and Wonder Woman are commiserating how annoying things are and, well...
Yep, full on smooching!
This really showed that all things were possible in the New 52. This new power couple (pun intended) even got their own series for a while.