We don't know what he truly wants now, and even less what he might want when he is a full adult because even he might not know that yet. Perhaps he wants to run the first Mars colony, not the USA - that would probably leave a larger mark on history than being just one of the USA presidents - or become a businessman, not a politician, especially if the USA is doing well when he becomes old enough that he could consider presidency.

And in the end it's not about we want. It's about what HE wants to do with his life. His life, he decides.