What could have been the most insightful moment into the very nature of superheroes since that thrilling final scene in The Dark Knight occurs in the final act of Wonder Woman, when Diana Prince (Gal Gadot) realizes that evil carries on despite her executing the main baddie.
I say could have because the movie flirts with a very interesting idea that ultimately falls flat: superheroes are not just different from humans because they are stronger, but because they believe goodness can eventually overcome evil. If heroes did not believe in such a lofty ideal they would not be superheroes to begin with. Superheroes exist to achieve and aspire to heights us mere mortals cannot. That is why they punch Hitler in the face and stop a nuclear bomb at the last minute. They serve as inspiration into who we should strive to be.
The moment Diana Prince learns that the people she is trying to save are the same ones that take glee in annihilating their neighbor should be painful. It should illustrate that perhaps humanity is not worth saving after all. But that superheroes, because they are so much better than that, can see past our flaws and into the other side of our nature: the one that loves, laughs and finds the horrors of wars repugnant. Unfortunately it does not (settling for another slo-mo CGI trope ridden extravaganza), but the effort, like the heroine herself, is still noble.