Watching the USJ arc again is vicious. The kids are terrified out of their minds and have to watch their teacher be disfigured in front of them. Some of them have their first near death experiences. They're 15.
It's the horror story at the surface of the event.
But on this watch I noticed how sheltered, dependent and oblivious Tomura was at the time.
He's technically an adult but everything about him screams "grooming victim deliberately kept isolated from the rest of the world".
Don't get me wrong, Tomura is highly intelligent, competent and has clear combat experience. He also gawks at how cool Eraserhead and how powerful the kids are. He's surprised at All Might saving Katsuki like he's never seen Japan's number one celebrity in action before.
And when All Might defeats Nomu, he's genuinely distraught like it's the first time since he was five that he loses a pet. Although he's 20 years old now, he needs Kurogiri's help to emotionally regulate after their original plan fails.
And sure, he wants to kill All Might but later, in his mall conversation with Izuku, he seems like he's still working out the why. At the USJ, he spouts things about government oppression and heroes and villains being the same. Both are valid criticisms of hero society but he never brings them up again. When USJ!Shiggy is called out on it by All Might, he even admits that he doesn't actually care about what he's saying and only looks forward to the violence of it.
He hates All Might but clearly doesn't know that he was the one who crippled and almost killed his beloved master.
The whole situation is odd because usually a new villain's appearance should make them look scary and give us a good first idea of their motivations. But Tomura's reasons for killing All Might seem jumbled together and incongruent because they are.
AFO wanted Tomura to become a good vessel instead of an independent successor: The USJ was likely supposed to get rid of All Might for him (wouldn't want to take the risk of involving himself) and introduce his new body to the world.
In this context, what Tomura says and wants in this arc conventiely overlaps with the things AFO needs him to say and want.
Tomura's named reasons for killing All Might are vague because AFO intentionally left him in the dark about his century long feud with the users of OFA. All Might, for example, is weakening but Tomura has no clue that it's because of the injury his master gave him 6 years ago.
The scene after Tomu and Kurogiri flee the USJ is most emblematic of this: As soon as Tomura tells him about the annoying kid with a power similar to All Might's, AFO understands that OFA has changed it's holder. Tomura just keeps bleeding out on the floor.
I'm certain that afterwards, AFO subtly encouraged his grudge on the brat that kept him from killing All Might.
And sure enough, by the time season 2 and 3 roll around, Tomura's developed a full-blown obsession with Izuku and has him on his personal kill list. Killing All Might, on the other hand, has been deprioritized in favor of causing general societal destabilization.
Until now, I never realized just how deep AFOs manipulation runs. I think more people need to add him on Bnha's list of 'Abusers whose abuse was never properly recognized by anyone least of all their victims'.
All of this also explains, why Tomura was so terrified of AFO leaving him in Kamino but then experienced some of the most impressive character growth in all of Bnha.
