Obito has PTSD - Kishi should work for Hollywood.
Anyone think Obito's back story is strangely playing out similar to soldiers who come home from war? Countless movies have been made about this stuff. Kishi taking a note from Hollywood? This is "sort of" a theory, but more just an LOL. Bare with me...
I will be using "Soldier" in place of "Obito"
"A soldier is sent to a far land to fight to protect his country from the enemy. During the war he is killed protecting his friends. During his last moments he asked his best friend and comrade to protect his woman. His comrades went home but little did they know he actually survived and ended up being taken captive. As soon as his wounds heal the soldier spends all of his effort and time to find a way to get back home to his friends and family. The only people he has to live for. He does "Whatever it Takes". Including cooperating with the enemy. During this time he discovers the enemy plans and needs to warn everyone. Finally, after a long journey, he fought his way home. Only to discover that his woman died. His entire reason for staying alive was to get home to see her. The soldier is emotionally shattered. He doesn't know what to do. He is in Denial. Denial turns to depression as he gives up on love, life, and the world and everything hes fought for. He realizes the world is an ugly place, and will never get better. His depression quickly turns to Anger when he realizes that the friend he trusted her life with "let" it happen. Now he wants revenge."
(Switching to Naruto for ending)
Needing revenge on his friend/the world, Obito seeks power. He turns back to the enemy/madara and cooperates with the plan. He is given the tools and training needed to succeed. But first, he has a vendetta towards his hometown and Kakashi. The source of all his pain, the ones who killed his love. He attacks the city. Kill two birds with one stone. Destroy the Leaf and obtain the Kyuubi. This ultimately failed, but nothing changed. The original enemy plan is still underway. (Insert Naruto Chapter 1)