This used to happen occasionally during the cold war. US/NATO defecting to the USSR didn’t happen often, but it did happen occasionally.
You’ve already gotten read on that take on the military, so I’m not going to bother with that. I will say that it seems like this young person has some mental and behavioral issues, given his rank at his age and his disciplinary history. I would think he’s not someone who tends to make sound judgments or think things through.
In general, the military tries to actively avoid people with these kinds of issues, and will generally not reward this kind of behavior when it comes up. There are a lot of things you can point a finger at the military about with regard to behavior toward civilians or abuse within the ranks, but in this case it looks to me like things were more or less working, to the point that he decided to run away and join the circus.