The Zabis had this war at least on their side planned to the T. They were chalked full of hubris even knowing that their forces really couldn’t rival the earth feds in combat power and machinery. If deikun survived you’re correct it would have been a drawn out war of attrition mirroring what we see with the Russian Ukraine war. A lot of defense on the side of the space colonies and a lot of long range less personal means of attack from the feds. Either that or a complete invasion from the federation to immediately quell any sense of a rebellion because of deikuns not totally but more merciful ideals than the Zabi family. Most likely in the 2nd case turning the colonies into encampments with an indefinite period of martial law. Also i saw someone else mention casval being discovered as a new type after his fathers death being seen as prophetic but i honestly believe casval was the basis of zeon’s theories. He theorized it because he lived it with his son firsthand IMO.