The attack on Pearl Harbor made many people hate and fear Japanese-Americans, worrying that they might be spies for Japan.
The attack on Pearl Harbor by Japanese forces was the first attack on American soil in a very long time. It made people very angry and they took out their anger on Japanese Americans. Jeanne and her family have no idea what Pearl Harbor is. They have never heard of it, and until the Japanese bomb it, Pearl Harbor has no meaning to them.
That night, her father burns his Japanese flag and all papers that might show he has ties with Japan. As Jeanne noted, the “precautions” did not help. Her father was a target.
He was not only an alien; he held a commercial fishing license, and in the early days of the war the FBI was picking up all such men, for fear they were somehow making contact with enemy ships off the coast. (ch 1, p. 7)
So though the family had no Japanese military connections anymore and no involvement in Pearl Harbor, they lost everything. The American government rounded them up and stuck them in an Internment Camp, to protect America from them until the war with Japan ended.