I think that it really attests to how much Changez did love America that he chose to stay for as long as he did. The Reluctant Fundamentalist is about a young man who comes from Lahore, Pakistan to the United States to study business. He is in a difficult situation after the terrorist attacks of 9/11, partly because he lives and works in New York City and many of the people he encounters assume that all brown-skinned Middle Eastern people are threatening to America. Changez loves the opportunity and freedom America has offered him. He has attained a world-class university education, has an excellent job, and gets to travel to exotic places—what more could he want? Despite the luxuries life in America offers, Changez can never really integrate and "pass" for American. His skin color, his beard, and his accent mark him as different, and people judge him for these things.
Even though Changez had no personal connection to the terror attacks of 9/11, and despite the fact that Pakistan was not involved in these attacks, he is still seen as a threat. Others mistake his identity as something that makes him complicit in or in support of attacks on American lives and values. Throughout the book, a reader may question whether this is actually the case. Changez admits to smiling when the 9/11 attacks occurred, but does not fully explain why he feels happiness at this event. Perhaps he was glossing over some support of terrorism in the rest of the book, but I think it more likely that he felt the attack was somehow deserved because he had been judged for his ethnic identity even prior to the attacks. Maybe he saw it as an attack on the corrupt business world of big American cities.
Whatever Changez' true thoughts, the author has purposefully woven a narrative where we cannot really discern whether Changez was in support of Islamic terrorism. What we do know is that he loved the prospect of America, but was hated by her people.