My experience with these matters is 50 years old, so perhaps not worth much.  In college, I talked at length with Navy recruters.  Since I always wanted to fly, I was investigating the pilot program.  I asked about what happened if I could not make pilot, and they said perhaps navigator.  Still flying, so didn't sound that bad, I was really getting interested, then read the fine print, if there was ever a declared war or people with my navy taught skills were needed, I was subjected to being called up for the rest of my life.  I might have been willing to go for 20 years, but that clinched it for me not going in that direction.

My point in telling the story, is be sure you read the fine print carefully, the military is well documented with putting people in areas they are not prepared educationally to go.