IMO the only point to this whole thing is to show that the army should not be deploying anyone to an area they are sympathetic with. Would have been like putting 2nd generation German farm boys from Minnesota & North Dakota on the front lines against Germany. Just not a good plan.
Be in the army, yes, if that's what his choice is. Use him to help understand the language, the culture, etc. But be deployed over there knowing that he's Muslim and that he's not happy? Sorry but someone's not to bright.
Yes there were some Americans of Japanese descent used in the Pacific, but they were all their by choice.
And I think they were watched pretty closely.