Originally Posted by BatLobsterRises
And not only that, but what Jonah Nolan said about it is that, it's too easy to just say Batman is going out there fighting the most violent criminals in Gotham without taking life. From a writer's perspective, they felt they had to challenge that notion in order for Batman to grow as a character. Enter The Joker. The whole thing in TDK is Bruce has to realize that regardless of his intentions, his actions do bring about the deaths of others. He's waging a war...there will be casualties.
And where's his arc? Batman STILL hesitates to kill dangerous criminals and terrorists after everything that happened in the previous movies.