I'll Remember April (1999)

A Japanese submarine off the US west coast in April 1942 is forced to dive quickly, leaving one sailor outside. Americans of Japanese ancestry face hostility and "relocation camps" while Americans of German ancestry don't. Four preteen boys, one a fourth generation Japanese American, play soldiers in the woods and help "patrol the coast". When they come across the sailor unconscious in an abandoned factory, they're in doubt of what to do. Their attitude towards their "POW" changes when he saves one of them from drowning.