Originally Posted by
kalorama
To me it all comes down to one basic question, asked from Tony Stark's perspective: If the Accords had been in place prior to the events in AoU and all of the Avengers (including Cap) had been operating under its provisions, how would that have prevented what happened in Sokovia? As a guy who claims to be a futurist, Stark would have to know that it almost certainly wouldn't have...
So there's really no credible story or character-based foundation by which the outcome in Sokovia would be enough to spin him in the opposite direction.
The Accords aren't just about prevention, but about accountability as well.
1) It would've been up to the UN to call the Avengers to Sokovia.
2) The Avengers would be held partially responsible for the destruction, and all the dead children.
Tony is every bit the "I'll do what I want and you can't stop me", but he's also a human being. He changes his mind, he experiences regret - he feels. He knows he isn't perfect, and he can be compelled to see his mistakes and to right them. The entire reason he became Iron Man was to make amends for making weapons and war-profiteering.
For me, the reasons are there.
But I do wish we had another movie before this one to explore them further. I enjoyed that aspect of Iron Man 3, and breaking up with Pepper is too big of an event to happen off-screen.