However, he wouldn't hold back.
If the Hokage of Konoha were killed by him at that time, he would continue his method of "pain and peace" —
Since pain is easily forgotten, he would constantly inflict pain, ensuring that the world dare not forget.
If the world became numb, he would give them a glimmer of hope, allowing them to quietly grow, only to later annihilate them again, leaving just a trace of hope.
In this cyclical manner, the world would tend toward peace, and people's hearts would not lose hope and become insensitive.
If one day the "seed of hope" truly burst forth and overthrew him, he would willingly accept it, for by then, the pain would have lasted for centuries, deeply engrained and passed down through the spirit's lineage, surely preventing any further wars.
Nagato.
It was still that Nagato who wanted the world to feel pain.
