Sometimes when you make a promise it's really just a promise that you'll do everything you damn well can; sometimes when you make a promise, it's another way of saying you won't ever let go. It's what it meant, years ago now when Rhodey had found Tony in the desert and he'd said that the next time he was going to ride with him.

He wasn't and isn't infallible, that wouldn't have necessarily stopped Tony from getting kidnapped. But they needed to believe it would. "I know you will, sugar pie," he says. "I know."