The Sasuke Retrieval mission was a success and everyone went back to being happy and acting like nothing happened.
Sasuke is let out of punishment scotch free and was worshiped like a god, while Naruto was treated like dirt and ended up being ignored. When everything seemed to have settled down, something sets the blonde off and he ends up leaving his home in the dead of the night.
Four years later, when a war against Kuno and Iwa threats to destroy the Leaf, who will they turn to when nether Suna not Kiri will help? On top of that, why is the new Mizukage insisting that they will not get involved with Konoha?