This was the thing about Japan: she had never been there. Her parents had told her for her entire life that it was important to be American.”
-- Narrator (chapter 1)

Importance: The author is introducing the characters. The fact that Hanako has been taught to be American is an important part of her character and of her parents' characters. The idea that she is now going to live in Japan is the first evidence of the fact that she will struggle to figure out where she belongs.

The whole time in camp, she had dreamed of when they would be let out to work hard and start all over with nothing. Having nothing was not as bad as not having the chance to work for more."
-- Narrator (chapter 5)

Importance: Hanako has a strong work ethic, thanks to the years she has already helped at her father's restaurant before the war. She is more than willing to work...