In the Naruto Anime Series, Harshirama Senju and Madura Uchiha after prior to the First Great Shinobi War created the Village Hidden in the Leaves. The vision that Hashirama Senju has for the village is called the “The Will of Fire.” The Will of Fire states that everyone living in the Village Hidden in the Leaves is family and everyone will be willing to lay their life down for any other in the village.
The Will of Fire is one of those nice bedtime stories that is told to young leaf shinobi before being tucked into bed. Harshirama Senju’s goal was to create a system that would replace the infighting breed from clan warfare and create a system where children would not be sent to war. Harshirama Senju’s Will of Fire ignored how the Senju Clan at large felt about the Uchiha clan.
After years of war, the Senju Clan viewed the Uchiha Clan through hate-filled eyes. In the eyes of the Senju, the Uchiha Clan was the enemy that had murdered their family for years. This can most clearly be seen in Hashirama’s flashback where he tells Tobirama Senju that he is going to make Madura Uchiha Hokage. Tobirama scolds his brother Hashirama Senju and then gets the Village Elders to make him Hokage. Madura saw this act as foreshadowing the oppression and destruction of the Uchiha Clan by the Senju. In climatic battle, that followed Hashirama Senju murdered Madura Uchiha to protect the Will of Fire. The seeds of distrust and hatred between the Senju and the Uchiha run to deep for any sincere family-relationship to exist between them.
Every Generation of Senju kept the Uchiha Clan at arms length , which culminated in Danzo ordering the destruction of the Uchiha Clan for ” Security.” Even though Shisui Uchiha planned on using his Kotomatsukami, a mind controling techique on Fugaku Uchiha to end the coup. Danzo’s response to this was to have Shisui Uchiha and the entire Uchiha clan killed in order to ” end” their threat. Then he had Orochimaru make him an arm and implanted the Uchiha’s Sharingans into it. The Third Hokage found out and then allowed Danzo to remain free and continue to operate in the shadows. The lack of justice, for the Uchiha lead Sasuke Uchiha attacking the Villiage Hidden in the Leaves 17 years later when he found out the truth of his clan’s extermination. If the Senju had treated the Uchiha like family the various Uchiha conflicts would have never taken place.