Nero calmly strode through the yellowing corridor of the rotting asylum toward the control room. At the moment, Bane didn't know it, but he was now eating crow. As a lieutenant in the League of Shadows, Nero had warned Bane to completely eradicate both Batman and the police. No, the masked man told him. All he needed to do was to break the Bat, both body and mind, and leave him in the pit, which pretty much left him as good as dead. As for the police, Bane felt it was vital to leave the false impression with all Gothamites that he was merciful; the police, he argued, were just as powerless at this point as the Batman was.
Now, as per Nero's prediction, Batman wasn't just back in action, but he had freed the police and was leading them into battle against Bane's army in an effort to foil their plot to detonate the fusion device. Nero knew full well that even if the League prevailed over the police, Batman would find a way to save the city from the meltdown, just as he had prevented Ra's