In the beginning of the novel, Changez is rather innocent and naive. He talks about arriving at Princeton, and how he thought, "This is a dream come true. Princeton inspired in me the feeling that my life was a film in which I was the star and everything was possible." When he is interviewed for the position at Underwood Samson, the interviewer, Jim, calls him "Wildly overoptimistic." This seems to sum up Changez's youthful identity. He believes in a world where all possibilities are open. He says, "Princeton made everything possible for me." He didn't see the flaws or the negatives of a life in America right away.

Slowly, however, Changez starts to become resentful of American culture and life. When he is confronted by ignorant Americans who make assumptions about him based on his nationality, he describes the "typically American undercurrent of condescension." He contrasts his lavish experiences with Underwood Samson to his childhood, where he "learned to savor the denial of gratification—that most un-American of pleasures!" He becomes more and more apt to criticize the country. When he feels something like pleasure as a result of the events of 9/11, he is perplexed because he takes no pleasure in the death of innocents. However, he began to "tremble with fury" when America invaded Afghanistan, Pakistan's neighbor and a fellow Muslim nation. Changez experiences more ignorance and hatred of "greater intensity" as a result of his skin color. Worse yet, when he returns home to Lahore, he realizes,

I had changed; I was looking about me with the eyes of a foreigner, and not just any foreigner, but that particular type of entitled and unsympathetic American who so annoyed me when I encountered him in the classrooms and workplaces of [the] country's elite.

Who is he? Changez wonders. He says, "I lacked a stable core. I was not certain where I belonged—in New York, in Lahore, in both, in neither [...]." He thinks that his own identity has become "so fragile." Soon, though, he begins to realize that he "had always resented the manner in which America conducted itself in the world; [the] country's constant interference in the affairs of others was insufferable," and he begins to act not with America anymore, but against and in spite of it. His life in America resulted in a temporary loss of identity; he came to America with hopes and dreams that all felt within reach—these defined him. Eventually, he leaves America, determined to "advocate a disengagement from [America] by [Pakistan]," and recognizing that the innocent civilians killed by America are only seen as "collateral damage" to the American public. Changez rebuilds his identity in opposition to American culture instead of in support of it.

One way in which Changez's sense of identity is altered over the course of The Reluctant Fundamentalistis that he becomes more jaded about the world around him.  In the exposition of the novel, Changez is much more willing to embrace the Western world and the possibilities in it.  Whether this comes in the form of accepting the potential of the promise and possibility of what America can offer, what an Princeton education gives, and life at Underwood Samson, there is a greater possibility to accept what life has to offer.  

The experiences that are synthesized after the events of September 11 cause Changez's identity to become increasingly jaded. There is a greater acceptance of  the darker aspects of Western reality.  Changez embraces a more "fundamentalist" position because of this.  In a distinctive manner, Changez does not really accept the fundamentalist position because of what it features in terms of its outlook on life and the world.  He accepts it because of his discontent with the world as he knows it.  For this reason, he is a "reluctant" fundamentalist.  It is in this light where one sees how Changez's identity has changed from a position of being able to see the promise and possibility intrinsic in the world to one that is more skeptical of it.