Changez finds his identity over the course of the novel because his final incarnation seems to be the one with which he feels the most comfortable, the one that feels the most genuine to him. Throughout the book, Changez gradually defines his own identity more and more against, or in opposition to, an American identity. Instead of continuing to think of America as a land of opportunity or as "a dream come true," as he did when he first arrived at Princeton, he begins to become aware of and irritated by the "American undercurrent of condescension" with which he is treated. When he travels to the Philippines, Changez notices the obvious dislike of a local driver, and he begins to feel as though he is "play-acting when in reality [he] ought to be making [his] way home, like the people on the street outside." He looks at his colleague's blond hair and blue eyes and realizes how completely "foreign" to him this man looks.
Soon, Changez realizes that the pleasure he feels when 9/11 occurs further differentiates him from his friends and associates, and he feels it because he "was caught up in the symbolism of it all, the fact that someone had so visibly brought America to her knees." The more of American life he witnesses, especially post-9/11, the less he likes it. He says,
America was gripped by a growing and self-righteous rage in those weeks of September and October . . . ; the mighty host I had expected of [America] was duly raised and dispatched—but homeward, towards my family in Pakistan.
His resentment of America begins to build. It grows when he is called a "[expletive] Arab" and almost engages in a physical and violent altercation with his attacker. Soon, his beard becomes, to him, a protest on his part, "a symbol of [his] identity," and he no longer wishes to "blend in with . . . [his] coworkers." Little by little, Changez finds more and more to dislike, more and more with which to be angry in America, and by the time he leaves the country, he realizes that "the lives of those of us who lived in lands in which such [terrorist] killers also lived had no meaning except as collateral damage." When he realizes that finance is how America asserts its control, he no longer wishes to be a part of the financial world; he goes home to Pakistan and takes a job at a university, making "it [his] mission on campus to advocate a disengagement from [the United States] by Pakistan."
Over the course of the novel, then, Changez seems to define himself, bit by bit, in opposition to those aspects of America that he begins to hate, personally and then professionally. He gradually comes into his own identity by the book's end.