In The Kite Runner, why is Amir afraid to be Hassan's true friend, and why does Amir keep testing his loyalty?
Amir was simply unable to be Hassan's true friend. Amir was filled with insecurity and self-hatred. He admired his father's courage, but felt he could never live up to it. Amir lived in great fear. Hassan, who was small and weak, fought fiercely to defend Amir from the bullies, but Amir watched silently, afraid to act, as Hassan was violently attacked by the same gang. Hassan's courage made Amir feel great shame.
As a result of these feelings, Amir was compelled to exercise his power and control over Hassan, who was a servant. Growing up, they became close companions, but they were never equals. Amir abused Hassan and treated him very cruelly because Amir felt such contempt for himself. Being mean to Hassan made Amir feel better about himself. He punished Hassan for his own self-hatred. However, when Hassan remained Amir's loving friend, despite being so mistreated, Amir's shame and guilt only increased, and his destructive behavior continued.
Amir knew he did not deserve Hassan's love and loyalty. By mistreating Hassan, Amir was subconsciously trying to drive him away. Finally, Amir does drive Hassan out of his father's house permanently when Amir can no longer live with his guilt and shame for failing to protect Hassan. For Amir, Hassan had become a constant reminder of how worthless he felt himself to be.
Amir is a Pashtun and understands the social restrictions concerning relationships with the lower-class Hazaras. Despite the fact that Hassan is Amir's close friend, he is hesitant to acknowledge his friendship publicly, because it would be considered taboo. Amir is also jealous and envies Baba's admiration for Hassan. Amir desperately seeks his father's attention and understands that Baba prefers Hassan over him. As a result, Amir ridicules Hassan and does not include him in activities with Baba. After Amir witnesses Hassan being raped by Assef, he does not intervene and feels extremely guilty for not helping his friend. When Hassan refuses to retaliate against Amir, he begins to test Hassan's loyalty because he cannot comprehend how a person can be so genuine and pure. Amir understands that he is a sinner and tests Hassan's loyalty in the hopes that Hassan will retaliate and punish him. Essentially, Amir wants Hassan to retaliate in order to redeem himself for neglecting to intervene while Assef raped Hassan.