After Ozai ascended to the throne, he immediately began suppressing Iroh's influence in the military, making the generals choose sides, then promoting his own men and striking at Iroh's.
As for the particularly stubborn ones, Ozai could only help them "die for their country," just as Zuko had heard in the council chamber: by sending those troops out as human bait.
Faced with such naked oppression, people naturally would not sit and await death, and so the Rebel Army was born.
Another of the Fire Nation's Firebending Masters, the former admiral Zhengzheng, was now a member of the Rebel Army as well.
After the Rebel Army was founded, not only Iroh's supporters but also people dissatisfied with Ozai's methods joined one after another, operating in various places. Though small in scale, they had the advantage of being troublesome.
And in sending him, Iroh's disciple, to deal with an organization bound to Iroh by a thousand tangled threads, Ozai's intentions spoke for themselves.
Ozai clearly wanted this operation to put him at odds with Iroh's faction, thus binding him firmly to his own ship.
Call him full of cunning schemes or call him a seasoned schemer; either way, the facts told Kahn that Ozai really was not as easy to deal with as he had imagined.
Before he could even plan how to deal with Ozai, the man had handed him this enormous problem first.
So the question was, how could he break out of this trap?
Kahn instinctively wanted to ask Iroh for advice, but then remembered that he still could not enter the Spirit World, so naturally he had no way to meet Iroh.
But then he realized that perhaps he had relied too much on Iroh over the years.
Whether now or in the future, Iroh could not