Are you suggesting that religion was central to Japan's Pacific War? You're thinking ahistorically, trying to read the present War on Terror into a much different conflict.
If you knew about Japanese history, you would know that the Emperor authority was de jure but the de facto control was in the hands of a cabal of militaristic nationalists. If Hirohito was responsible for the war that terrorized East Asia in the 1930s and 1940s, why would we as the occupying power let him continue as Emperor?
Now, What do you think the religion of pre World War II Japanese immigrants living in America was? And if their religion was Japanese Shintoism, then who do you think their loyalty was to? This new foreign country, or the Emperor of Japan.
Your obvious xenophobia is repugnant. Furthemore, Internment was not limited to disloyal immigrants, but to "Americans of Japanese descent" (as my post made clear) regardless of their political loyalties. That's racist and that's wrong.