Disclaimer: I do not own Naruto.
Hiashi's Plan
The best laid plans of mice and men often go awry - Robert Burns
People who think that Hiashi does not know the minute details happening under his nose are wrong. Hiashi is acutely aware. He makes sure he is aware for if he were in the dark, he would not have survived for as long as he has as the Hyuuga leader. He knows of the plots to overthrow him if he advocates Hinata's right to rule because they think a weak leader will destroy the clan. He knows of the plans the council has of betrothing Hinata to Neji, in effect, making her a branch member. He knows of the affection his nephew has for his daughter and that Neji would be delighted to hear the news. He knows of the frequent visits same nephew pays to his other underage daughter, the one the council wishes to appoint as the official heir. He knows about Hanabi's manipulative streak, the trait that would make her a formidable Hyuuga leader. He knows about Hinata's intent to fight for the Hyuuga leadership, yet for all his ability to read people, his oldest daughter remains an enigma. What he does not know is why she would covet the position.
Some may say if a father knows that his underage daughter is performing sexual acts with her cousin, should he not step in to put a stop to that? What kind of father would not? Hiashi is that kind of father. He thinks that he is looking at the bigger picture, the greater scheme of things. The Hyuuga like to think themselves as masters of foresight. He does not put a stop to Neji and Hanabi because he thinks that they will produce a child of great talent, Neji having already proved his worth as a genius and Hanabi, having outshone her sister in terms of her abilities would be better genetic stock than Hinata. To Hiashi, Neji and Hanabi could produce the third generation heir before Neji is to be betrothed to Hinata. At least that was his plan.
