<p>The reincarnations mean they were blood brothers in former lives. As reincarnations, they were bound to befriend and have a fallout later.
</p><p>War doesn't make what Madaea did justifiable. He listened to his foolish brother and doomed him. And he has the nerve to blame others for it.
</p><p>His greater purpose was to be a toy. He read some tablet, blabbered about new plans and got angry that no one took him seriously. And despite all the shit he did, we're supposed to think he was some tragic anti-hero because his dumbass brother died in battle. The narrative is so blatantly oblivious to his characterization and hypocrisy. The bastard even gets to die peacefully with Hashirama the Naive near to him.
</p><p>I suppose it's too much to expect Kishimoto to not glorify the stupid Uchiha and focus on other characters. Wife of the first Hokage and grandmother of Tsunade, the first Jinchūruki of Kurama.
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