Why were the Japanese considered American's greatest foe in wartime?
they used methods that were unorthodox to the American soldierslike kamikaze
They were also the only ones to attack American soil.
It was feared that Japanese Americans would be more loyal to Japan, which was at war with the US during WW II, than they were to the US in which they lived. This was very unfair to the Japanese who had done nothing to demonstrate disloyalty to America, and the wartime internment of the Japanese remains a shameful blot on American history.