Typically, the military only pays off student loans if you're going into a specialized field. My son has a slot as a Marine Corps pilot when he graduates (December), and they're paying his off once he gets his wings.
Check out the Yellow Ribbon program that's part of the post-9/11 GI Bill. It's an amazing deal-beyond the cash for school (something like 50 large), many states let you pay in-state tuition regardless where you're from, or some privates give automatic schollys. I'm a Navy vet and WISH I had such a good deal, but I got out 17 years ago, so I'm under a different GI Bill. Not to mention, if you're going to be an officer, that is a huge soft on your LS app when you get out. I'd go Army first.
Also, on a side note, you wouldn't necessarily be in a "hot" theater unless you're going to be an infantry, mech or armor designator.