The U.S was bombed by Japan on December 7, 1941. After the war Roosevelt signed Executive Order 9066. This claimed that all ethnicities were not allowed in the U.S. for greater national security.
Japan surprise attacked our US Navel base on Oahu Island of Hawaii. On Dec. 7, 1941. "The attack on Pearl Harbor was intended to neutralize the U.S Pacific Fleet, and protect Japan's advance into the Dutch East Indies."
If the battle would have been fought differently the U.S would have probably won. If we saw them coming & been prepared, we would have less killed or injured.