One of the biggest regrets of my Army career is not trying to go 18 series while i was a hard charging, non-kid/wife having soldier.
Now, with the wife and kid, and me pushing 30, I don't think i can.
I have a nephew in the Air Force - a snake eating Pararescue Jumper (PJ). They do scary stuff all the time. And, they don't get to pick the "when". Someone is down and injured, they go. Now.
Except... He's pushing 40, having joined up at 18. He just had back surgery a month ago to fuse several vertebrae. Nearly *all* his discs are shot, after jumping out of every flying thing in the AF inventory, carrying heavy loads and people, and generally abusing his body for 20 years.
It is very definitely a young man's job. And, shouldn't necessarily be a career. I suspect, though, that lots of things seem pretty boring after a few years in something like that.
jb