Look. I really don't like John Walker but I totally understand his anger during his trial (which wasn't even a trial, the decision was already made).
"I only ever did what you asked, what you told me to be and trained me to do, and I did it. And I did it well !"
He works for the Army since so long and he obeyed orders properly and he rose to the top by doing so many unspeakable and horrible things ( "three badges of excellence to make sure I never forget the worst day of my life" S1:E4). I'm sure he has hard time to sleep at night but he did everything he thought was right -everything they told him was right- and he's still here. He still waits for new orders and he's still ready to follow this path because that's what he's supposed to do.
"You built me."
They gave him a gun, an uniform, a team, then the shield with the star. They gave him orders and plans. They made him. They built him. And now they're throwing him away for a single mistake (a big and unforgivable mistake I agree with that) as if he's a broken doll. But they built him broken therefore it's as much their fault than his.
He lost his best friend because what he was conditioned to see as a dangerous extremist who has to be eliminated quickly couldn't control her strength, and now he lost his shield (THE SHIELD THEY GAVE HIM) and his title (that he didn't ask for) and the public's trust (who praised him a few days ago), and his place in the government army (who BUILT HIM PIECE BY PIECE).
I'm not going to say that he's just another Bucky who doesn't deserve that hate- because he does deserve it. I'm saying that he has the right to feel angry and betrayed by the very same society he used to fight for, by the government he was actively trying to protect when he made that mistake. He's wrong, but they built him in a way he can't be right. They made him broken then got surprised when he broke and hurt other people, and they threw him away.
