In some alternate universe, maybe “The Iron Giant” follows Brad Bird’s original plan to have the Giant die at the end — luckily, McCanlies realized that he simply couldn’t let that be the last we saw of him. Indeed, ending with the triumphant callback to the reassembling sequence from earlier in the film does nothing to undermine the climactic sacrifice. What matters is the Giant’s memory of Hogarth’s words while flying out into space to meet the nuclear warhead, recalling that, “You are what you choose to be.” His choice is the natural endpoint of his arc, not his death.
And while the most cynical interpretation of the ending is that it leaves the door open for sequels (which obviously never happened), the tone and spirit of the film all but demands that the Giant survive. Even when it evokes “Bambi” with the deer scene in the forest and opens the Giant’s eyes to the inevitability of death, “The Iron Giant” still manages to ride that impossibly tricky line of balancing sobering, adult-minded themes (a constant in Bird’s filmography, as we saw in “The Incredibles”) with that childlike sense of wonder infused in Hogarth’s impossibly wide eyes and the Giant’s own understanding of who and what he is.
So when the stray bolt (the only part of the Giant recovered from the explosion) begins to jump around in Hogarth’s room and makes its way to the window, everything clicks into place. We’ll never know if the Giant blasts off to another planet entirely, safe in the knowledge that he isn’t a gun, or if the two ever reunite for more adventures. Either way, he has the rest of his life to choose — and keep choosing — to do the right thing.