Earlier quoted context omitted.
I think you are attributing a lot of what goes on to choice - war has a poor track record in this regard and soldiers are often recruited very young and/or conscripted. Even the US recruits soldiers defined by the Convention on the protection of children (below 18). Schools are used for recruiting in many places. This aspect of war is really sad - giving kids and young adults guns and sending them off to shoot people…
I'm talking about the men in this article. Both of them were career military officers. It's fair to say that that was their choice. Certainly there's propaganda that goes into recruiting naive young people in the US, but it's quite a stretch to equate that with child soldiers. I chose to enlist and so did everyone I served with. The vast majority of us do not regret it or feel that we were conned.
The US has signed The Convention on the Protection of Children. This agreement defines a child solder as one below the age of 18.
You may not feel conned but it’s not just about you - it’s the places they go, the decisions they make and the population they supposedly protect that should also matter.