I had that same thought - IMO translators should be held separate from the Armed Forces. Remember the recent threat at Ft Jackson.
I have to profess ignorance as to whether German Americans or Japanese Americans served during WW2. Hmmm. Now I have to go look it up.
I'm certain that Americans of Japanese extraction served during WWII.There are at least a couple of documentaries on that subject that I've seen.What I saw suggested that they served bravely and admirably.I *think* I recall that they were deliberately assigned to Europe rather than the Pacific but I can't swear to that.Never heard anything either way about Americans of German extraction.
The Nisei were quite valiant and eager to prove themselves American.
Look to 442nd regiment for Japanese Americans serving in WW11.
I amfairly certain that German americans fought also although not in theuir own regiment. I could be mistaken on this point though