I don't think I agree about why Jack refuses to treat Ben - I think he was genuine in that he's trying to do what he's supposed to do, and there's also the knowledge that no matter what choice he makes, Ben will survive. I do agree that we're meant to see Jack's choice not to act as a bad one, in that whether or not he knows Ben lives, it doesn't absolve him of the moral responsibility to help a suffering child. Jack is being passive-aggressive and justifying not wanting to treat Ben again by deferring his conscience on to "the will of the island." But I don't think Jack was deciding that Ben had to die the way Sayid was in shooting Ben in the first place, because Jack has more knowledge at this point. He believes that Ben will live no matter what choice he makes.

I'm much more sympathetic towards Kate, Sawyer and Juliet choosing to act to save Ben, but I do love that we specifically see Kate and Sawyer make a choice that will in some way contribute towards Ben "losing his innocence" and becoming adult Ben. So Sayid, Jack, Juliet, Kate and Sawyer all have some involvement in Ben becoming Ben, although ultimately I think it's down to Ben's own choices as an adult. I really can't wait to see next week's episode though - the idea that Ben himself thinks he should be judged is extremely intriguing.