“IMHO, he has fulfilled his duty. We have a lot of troops in Germany, Japan, and other areas we can rotate in.”
IMHO he will have fulfilled his duty when the Army tells him he has fulfilled his duty.
It’s tough, I know — I had a couple of combat tours myself some years ago — but, active duty personnel don’t get to negotiate their orders, they follow them and like it. He knew the rules before he took the oath.