They were fought in combat; on land, sea, and air.
Russo-Japanese War happened in 1905.
First Sino-Japanese War happened on 1894-08-01.
Second Sino-Japanese War happened on 1937-07-07.
Manchuria
America held the Japanese in camp during WW2
An allied power during that war.
Not during the 20th century.
The Japanese
No
The Japenese were on the Japanese side in WW2
Most Japanese were interned for the duration of the war.
The Japanese-Americans were compelled to enter into internment camps .