"The Southern Raiders" have Zuko relapsing into his previous evil (ATLA Discussion)

I'm speaking about ATLA, so I feel like I shouldn't feel the need to warn about spoilers, but... yeah, this has heavy spoilers about ATLA.

"The Southern Raiders" is an extremely controversial episode amongst the ATLA fandom because of how it handles Katara's worst moments.

While the Gaang is preparing themselves to fight the Fire Lord, Katara is still distrustful of Zuko, due to Zuko betraying her back at the end of Book 2 and getting the Avatar almost permanently killed. Zuko asks her what he can do to make her like him, and she challenges him to bring their mother back, as Katara tried to bond with Zuko over their mothers when Zuko betrayed her. He answers back by opening the way for Katara to take revenge against the person who killed her mom, and she accepts. Aang tries to dissuade her, because revenge is wrong, but Zuko eggs Katara on and dismisses Aang, who ends up accepting the idea of Katara confronting the killer, while disapproving of her objective to kill him, and Zuko and Katara go around the world on Aang's flying bison Appa to look for the captain of the Southern Raiders, whom Zuko recognizes as Katara's mom's killer. When they invade the base, Katara forces the captain to submit using a waterbending technique called bloodbending which she swore off using due to the evil connotations of a technique that was invented to force people to submit against their will. That startles Zuko, who is seeing her bloodbend for the first time, and they figure out that the killer retired from the army a while ago. They go to his house, they ambush him, Katara pulls an Inigo Montoya and *almost* kills him, deciding at the last second not to because the man she set out to kill turned out to be a snivelling coward who instantly cowered before a strong opponent, and killing him would not be satisfying in any way that mattered. She ends up forgiving Zuko anyways because she learns the lesson that even though she doesn't need to forgive those who don't deserve it, getting worked up and resentful isn't worth it either, and she feels that Zuko teaching her that was worth her forgiveness.

Now, a lot of people talk about the dychotomy of Zuko, who had undergone a redemption arc about doing the right thing for the right reasons, egging Katara on and Aang preaching forgiveness and peace of mind, and how Katara dismissed anything that went against her vengeful mindset, including her own brother's grief.

But I want to add my two cents to the discussion, and claim that Zuko was experimenting a character regression.

People usually stop at the concept of Zuko being a villain who learnt the value of doing the right thing and stop there, but Zuko was a people pleaser. His father burnt his face to a crisp, banished him and made him do a wild goose chase for the Avatar, and Zuko gave everything he had to capture the Avatar. He said he wanted his honor back, but he wanted his daddy's approval. He was a people pleaser through and through, and even though he had an innate moral compass that refused to be molded by Ozai's raising, unlike Azula, who was amoral and was molded into sociopathy by Ozai, he still went against that moral code to please his dad.

So, when finally cutting ties with his father, denouncing his family as evil and giving up on the idea that his uncle would ever love him again after he betrayed him for his dad, he decides that the Gaang is the new community he wants to belong to, and he's desperate for their approval. Toph instinctively trusts him from the start because she has both the ability to sense he's sincere in his attempt to reach out and the lack of previous history with him. Aang begins to trust Zuko when he learns that Zuko has the same hang-ups about firebending that he has. Sokka trusts him when he helps him break out his dad and his girlfriend from the worst prision of the Fire Nation. But Katara is still not sold on his change. She remembers confiding in him and reaching out for him only for Zuko to almost literally burn her extended hand and betray her. So Zuko's desperate to please Katara and close the rift between him and the community he wants to belong to. And the only way he knows how to please people is to indulge in their evil. That's how Ozai taught him to please him and that's how Azula kept a close eye on him: His desire to please those he loves trumped his moral code until he couldn't conciliate that contradiction anymore and cut ties with his family. When Katara unwittingly offered him a chance to please her by enabling her worst impulses, he instinctively took it because he doesn't know any better. He was very relieved when Katara decided on her own to get over her own darkness and heal because of this.