Anon asked: You've said many times that Azula wanted Zuko home again and I do sort of agree but how do you explain her only helping him out at the end of book 2 instead of right away?
Let's say she brings him home when she first promised she would. What happens when they arrive at the Fire Nation and Azula has to tell her father that she went against his direct orders - and her list of justifications for it?
Hey, dad, I want my brother, the traitor, to come home.
Pretty please?
Love you?
"Best" case scenario: Azula is severely punished and her brother is thrown in prison. Worst case scenario: Ozai throws them both in prison and gets himself a new wife that can give him new children.
She can't bring him home at that point. Ozai will never allow it because Zuko isn't worth a damn thing in his eyes, and Azula trying to help him would only make their father wonder if he should get rid of her too. It doesn't matter what she does, Zuko is never coming back to the Fire Nation unless he captures the Avatar - and he failed to do that dozens of times, so Azula takes over that mission, because even though she loves him, she loves Ozai and their nation too, and capturing/killing the Avatar is in their best interest.
But then she manages to go to Ba Sing Se using a false identity, and it's taking over the city from the inside, is so close to defeating the Avatar, and even manages to find out about an invasion plan that would put their nation at risk… and her brother is right there as well. It's literally the perfect opportunity to bring him home, he just has to join her and help her finish what she started. And he does. And her list of justifications now?
They killed the Avatar, the biggest threat to the Fire Nation
They took over Ba Sing Se, the impenetrable city that their uncle had failed to conquer, and it's downfall essentially means they won the war already
They captured Iroh, who is the real heir to the throne and therefore a threat, AND who was also conspiring with their enemies.
And just in case their enemies somehow are still trying to fight back, here's the super secret plan they have to invade their nation during an eclipse, which would have literally cost them EVERYTHING if it worked.
Ozai cannot overlook all of that. Hell, we see in the show that he even started treating Zuko with some respect.
Azula didn't help Zuko out at the end of book 2 because she suddenly decided to be nice for a change or because she needed him for some evil plan - she did it because that was the first and likely only time she'd ever be able to, and she jumped at the chance immediately.