I feel the author's story about his transformation into the Anglosized American stands for a commonplace theme of "acceptance" and "fitting in." When many people come to America (Or a new country), they're instantly hit with numerous things that are different from their own culture (i.e. culture shock). It doesn't help matters any when stereotypes are built up about them and they are met by hostile neighbors, co-workers and classmates.
This desire to fit into a new country where they know no one and nothing can cause a person to conform, to leave the prominent parts of their culture that was once so strong by the wayside to fit into a completely different culture that they've been pushed into, thus the situation the author was put into. When in the town he grew up with, his culture was all he was surrounded by and loved, but slowly and surely turned into the "normal" American person that he was expected to be.
My response??: In a nutshell, it's easy to claim one will never lose their culture, but it is not until one is put in such a situation that it is tested. Being an immigrant is not easy and to survive and be who you are, some changes are necessary. Being an immigrant is never easy, especially when you're part of a culture with many stereotypes built up against it.