Jor-El's intentions revealed.

[InexorableWanderer]

Lest humans find the stones and use the "knowledge of the universe" to great destruction, Jor-El prepared a nemesis to annihilate mankind before it could use them. Jor-El considered two possibilities: Clark would rule evil, primitive mankind with the help of the stones; or Jor-El would annihilate evil, primitive mankind to prevent it from using the stones.

[Superdan13]

Maybe he meant, Kal-El would unite the stones and become the al knowing diamond geezer Superman is and become the leader of the world in the sense of the battle against evil or he would have to stop evil corrupt humans from having them he could do this with the 'Eradicator' But against all my wishes but I am torn between not wanting Zod based on the FACT he would after a few days of Sun bathing kill Kal and the awesome battle it would be and Kal would win based on the show being about him.