Warning! Spoilers ahead for Justice League #60
In recent years, a lot of focus has been put on the rivalry and enmity between DC's Batman and Superman. Largely brought on by 2016's Batman v Superman: Dawn of Justice, there seems to be a large belief that there's a constant tension between the two heroes even when they're not duking it out (even LEGO Batman told Joker that Superman "was his greatest enemy"). However, this is simply not the case in the present DC Universe, and the most recent issue of Justice League just hilariously pointed that out.
In Justice League #60 from writer Brian Michael Bendis and artist David Marquez, the Justice League are facing a new inter-dimensional threat in the form of the villain Brutus, who's also drawn the attention of Black Adam. In light of this, Superman wants to invite Black Adam into their ranks, as he's noticed efforts on Adam's part to be more heroic and operate on the side of the angels. As such, Superman wants to foster and encourage that desire by having Adam join their ranks. Once that's settled, the League responds to Brutus' latest attack, which was repelled by Queen Hippolyta.
As the League surveys and investigates the scene, Aquaman meets and chats with the crowds of civilians that had begun to gather, and he even signs autographs for a group of kids. Furthermore, the king of Atlantis also answers a few questions the kids have about the League, and it's here where he hilariously proves how ridiculous it is to think that Batman and Superman are always at odds with one another.
According to Aquaman, the Dark Knight and Man of Steel are best friends, and he thinks it's "adorable". He's not wrong either. There's plenty of evidence that Superman and Batman are incredibly good friends and care a lot about each other. There's a reason they're called the World's Finest. Nine times out of ten they have each other's backs, though that doesn't mean Batman isn't going to have a plan to take Superman down if the need arises. Batman is Batman after all, and that means he is always going to prepare for the worst...and expect the worst. However, Superman's goodness allows the Dark Knight to put a good amount of trust in the Man of Steel as an ally and a friend more than most, and having Batman's trust is understandably hard to earn.
The entire idea of Superman and Batman's rivalry seen in Batman v Superman was largely inspired by Frank Miller's Dark Knight Returns: an alternate future storyline that sees Batman coming out of retirement against the wishes of Gotham and the U.S Government, and Superman being ordered to take the Dark Knight down, having become the government's pawn. While it's certainly an incredible story (and has become somewhat pervasive due to being such a strong source for the DCEU films), it isn't reflective of Superman and Batman's current relationship as best friends, so it's fun that Brian Michael Bendis took time to make this clear through Aquaman in this new issue of Justice League.