Actually, John doesn't.He asks clark to hide himself till the right time to assist humanity. Humanity shouldn't be put in that much of pedestal either. If you go by goldenage siegel and shuster origin. Clark sort of starts protecting the weak cause that's just what he is. That's more appealing to me than Superman being a product of either set of his parents. Heck! I prefer the motorcyclist origin more where clark is a genuine orphan.I want superman to be the epitome of altruistic instinct and choices. I prefer his parents to have less role.