Originally Posted by Rust
Maybe Krypton is plagued by war (insert Brainiac-reference?) and it's custom that gifted children have to enlist to becoming future soldiers and military strategists and leaders. The war-council (lead by Zod) wants Kal-El because of his genes and specific potential, but Jor-El refuses and suggests "what if a child dreamed of becoming something other than what society intended". "What if a child aspired to something greater?"...
Something like that.
That would be an explanation I could probably get behind, but when I think about what Rust said, now I'm thinking it was a line recorded specifically for the trailer because it works so well with the shots of young Clark running around the yard with the cape and hands on the hips pose.