Khaled Hosseini's The Kite Runner tells the story of two young boys growing up together in Afghanistan in the 1970s. The boys grow up like brothers, but they are separated by differences in ethnicity, religion, and socioeconomic class. These differences lead Amir to act like a coward when he should protect his friend Hassan.
First, let's establish the larger historical and political context that informs the lives of the characters. The majority ethnic group is the Pashtuns, while the Hazaras are a minority that is mistreated and oppressed. The Pashtuns are mostly Sunni Muslims, while the Hazaras are mostly Shi'a Muslims. These fundamental differences in religious beliefs contribute to the Pashtun prejudice against the Hazaras. As a result of their supposed inferiority, the Hazaras are at the bottom of the figurative food chain: they do not have access to education and work as servants to the superior classes. In The Kite Runner, Amir and his father Baba are Pashtun; Baba is wealthy, respected, and influential. Hassan, on the other hand, is Hazara and he and his father work as servants in Baba's home. Ali grew up with Baba, like Hassan grows up with Amir, and even though there is a close emotional connection, ethnic, religious, and class hierarchies separate them. The early chapters of the novel depict a friendly relationship between Amir and Hassan, but Amir is a sensitive and somewhat weak child, and when he is challenged by those he perceives as stronger than himself, he caves. One such person is Assef, a bully who idolizes Hitler. Assef bullies Amir for being seen in public with Hassan and uses the stereotypical ethnic slurs against Hassan. Assef and his friends later sexually assault Hassan in an alley and Amir sees what's happening but does nothing to help. In these scenes, Amir takes cowardly refuge in his supposed ethnic superiority. He asks himself why he should care what happens to a Hazara. He sometimes even tries to trick Hassan to make him feel stupid simply because Hassan is, through no fault of his own, illiterate. The systemic oppression of the Hazaras allows Amir to commit sins against his best friend and excuse himself because of his "superior" status; however, Amir cannot escape the guilt that follows him throughout his life.
Later in the novel, Baba and Amir flee Afghanistan and eventually move to California to escape tyranny and violence in their homeland. Lower class people like Hassan and Ali, though, are not capable of following suit due to their lack of resources and connections. Also, by that time, Hassan and Ali have moved away because of Amir's behavior toward Hassan. Even later, the Taliban takes control in Afghanistan and Hassan is actually killed by a member of the radical sect. Assef, now a Taliban leader, takes Hassan's son Sohrab as his personal slave. The later chapters of the novel give the reader insight into the state of Afghanistan under Taliban rule: Kabul is in shambles and Hazaras are still victimized. People can be shot in the streets for even a perceived violation. Women's behavior is strictly controlled. Once Amir rescues Sohrab, the extremely complex process of adoption is depicted; there is no death certificate for his parents, so Sohrab cannot be adopted by Amir at first.
The Kite Runner as a whole provides a realistic and tragic illustration of political changes in Afghanistan as well as deep-rooted prejudices. These contexts contribute significantly to the tragic ending of Amir and Hassan's friendship and motivate Amir's redemption journey in the novel's second half.