Okada had to interrupt his studies, and he and his family were among thousands of American citizens interned at Minidoka War Relocation Center in 1942 as a result of Executive Order 9066.
Okada was taken out of the internment camp and recruited to the United States Army Air Forces after he completed a loyalty questionnaire which asked him to "forswear allegiance" to the Emperor of Japan.
He explored feelings among Japanese nationals, some of whom still held dreams of a return to Japan, and among their native-born American children, who felt conflicted about their identity but identified with the United States.
[7][10] John Okada's “No-No Boy” captures the injustice of incarcerating Japanese-Americans during World War II — and serves as a warning today for our own fractured society.
In 2018, Frank Abe, Greg Robinson, and Floyd Cheung published John Okada: The Life and Rediscovered Writings of the Author of No-No Boy.
[11] This volume, which received an American Book Award in 2019,[12] includes a substantial biography authored by Abe and based on interviews with Okada's family members and friends.