The thing was, Steve knew that Stark wasn't an idiot. That had been made clear time and time again. While he still believed that there was more to smarts than just being good with gadgets (and having a lot of money), Tony was sharp in more ways than that. Which made it even more maddening when he went and did something reckless just because he could. Couldn't he have swiped that information without basically painting targets on their heads at the same time?

"Yeah, and now Doctor Doom knows exactly who we are, and he knows that we stole his files." No, Tony had been the one to steal them, but seeing how Steve had been with him, he was just as culpable.

Steve realized that in a way, this was the result of them being very different people who worked in different ways. He wasn't one to follow orders blindly, but he definitely did so when it made sense. Whereas Tony seemed to break rules just because he could, because it would get him attention. Didn't he have enough of that already, when the news brought his name up at least once a week? Steve just didn't understand it.