How do the boy and his camp friends show more naivete than harmful intentions in some of their games and habits?

Many of the boy's activities, especially with other children, are the same as those of any children anywhere in the world. The boys play board games, and they also play soldier. When they shout things like "Kill the Japs!" their own heritage does not occur to them. Even when the boy walks below the guard towers and whispers "Hirohito," his actions have more to do with childhood curiosity than defiance or pride in national identity.