I can understand it more from a ratings standpoint. I'm expecting it to have some bloody battle scenes. A graphic gential mutilation scene might send it passed R territory. But who knows what the ratings board will allow, they are about the dumbest bunch of people allowed to meet together.
Doesn't need to be graphic.
Litte was shown in the "gimp" scene in Pulp Fiction but audiences "knew".
It can even be mentioned in passing reference or a text passage in the credits.
But the horrors of the ENEMY (and this is what the Japanese were) should not be downplayed and their justifications for war substaniated.