There seems to be a sense of gleeful abandon in the hate piled on Batman v Superman, with fierce denunciations of incoherent storytelling, excessive morbidity, unclear character motivation, and - worst of all - a lack of faithfulness to the source material.
Now, I’ll put this up front: I loved both Watchmen and Batman Returns, two films that get a lot of hate for being slow and dark.
Did Man of Steel earn dark? No. While I understand Snyder’s conceit that it was a formative Superman story, it’s implausible that someone who demonstrated such conscience in the middle act would have to murder someone to learn murder is never the answer, or realize that punching someone into a building might endanger innocent life.
For Batman v Superman, dark is earned. While Superman is still finding his feet, Batman has been at it for 20 years. He’s tired. He’s jaded. He’s lost a Robin and Wayne Manor. This isn’t the Batman of the mainstream comic - this is the Batman of The Dark Knight Returns. There are machine guns on the Batmobile. He’s been killing for years. And those crying foul over liberties with Batman’s principles would do well to read Frank Miller’s dystopian masterpiece: here we have a Batman broken by the cost of two decades of battle with nothing to show for it but ongoing crime.
Then this guy shows up who could stop any crime in an instant, but doesn’t. Yet he has so much power he can kill thousands by accident. How could a hero devoted to protecting the innocent possibly allow such a danger to exist?
That’s the surface part of Batman’s motivation. But as we see throughout the film, Superman’s very existence can damage the human psyche. Some worship him. Some see him as a hero. But for Bruce Wayne, who’s been frustrated by his own inability to end crime, he represents an invalidation of everything he is. With a veritable god around, is there even a point in being Batman? What were all his sacrifices for? Bruce Wayne turns to drink to quiet his constant existential demons, and his increasing brutality is just another inappropriate outlet. This is not a hero Batman anymore; this is one who must be reined in.
This film also addresses the question of whether Superman’s power is too much for one person to hold. While the MCU has many super-powered beings, as of the start of this film, DC has only one. Superman could kill us all, and we simply need to have faith that he won’t. Batman himself turned from a paragon of justice to someone who kills to get the job done. How could he be sure Superman wouldn’t do the same? And if he did, who could stop him? As (seemingly) the only other hero around, he has a responsibility to ensure Superman is either contained or destroyed. And nowadays, “destroy” is his natural choice.
This is why the story hinges on Batman’s faith in Superman’s humanity. While it could be argued that the transition is too quick when it comes, we must also remember that Batman is, though he doesn’t know it, seeking to reclaim his own humanity. The realization that he’s about to slay a man - not a god, but a man - who fears for his mother just as he feared for his own drives a nail straight into his heart. It may be contrived (what superhero movie isn’t?), but it’s not without logic or motivation.
As for Luthor, he has a similar existential problem. He doesn’t fear Superman thwarting some particular plan. The problem is, if Superman exists, what are his plans worth?
Luthor believes knowledge is power, and as one of the most knowledgeable people on earth, he’s at the top. Then Superman arrives and tilts the scales forever against him: no matter Luthor’s knowledge, Superman will always have more power.
You can see Luthor cracking during his library speech, as the thing that makes him feel useless stands there while he can do nothing. Nothing, except pour his mind into finding a way to destroy Superman, both eliminating the symbol of his inadequacy and proving that knowledge can defeat a god’s power.
And what kind of plan does he hatch? One that manipulates two heroes into mutual destruction while he prepares an insurance plan. It’s a complex scheme from a complex villain using only his intellect to destroy the most powerful thing on earth. It’s hard to follow, and should be, as it creates a worthy opponent for the detective Batman.
We must also understand that while we have a fallen Batman, we also have an incomplete Superman, traumatized by the idea that, despite his power, he’s unable to save his mother. That Batman refuses to help - and won’t even listen - drives this not-yet-self-accepting Superman to act in rage. The first appearance of Kryptonite is another shock. While the reaction is foolish, it’s set up by the story: only Superman’s humanity holds him back from killing Batman, yet the very symbol of his humanity is at stake, and the contradiction makes him prey to emotion.
This is not a film about physical goals, where villains want to steal something or destroy something or gain control over something. This is Dostoevskian: The characters’ actions have everything to do with their sense of who they are. For Batman and Luthor, Superman’s existence invalidates everything they ever thought themselves to be. And for Wonder Woman - who is, yes, important here - his dogged sacrifice represents a reason to fight for humanity once more. Her presence gives significance to his actions, and finally brings us around to what Superman can be at his best: the guy who does the right thing even when it’s the hardest thing to do.