Perhaps this is a baseless speculation, but I have a vague feeling that Chris set up the massacre five years ago to quickly advance in ranks, appoint his own people everywhere in the government and military and then continue the conquest using Mars, Uranus and perhaps others, while keeping them on the leash using Vendetta.

Adler is the only country that weaponised Astral. How would other countries create Mars and Uranus if they can't even enhance humans?

This guy kept their existence a secret after they got "killed" by him, it would make sense he's hiding even more. He can't simply be a hero. This just can't be as simple as that.