I served 14 years in the USN and 12 years in the USAF. In the Navy I was a cryptologist, and in the Air Force I was a chaplain. I retired in 2008 at the age of 51 and I am working in civilian life now (I am a congregational rabbi). If I didn't have kids
in college, I would be able to retire, period, and with reasonable comfort.
If you have a spirit of adventure, a desire to serve, and a temperament that allows you to give up some of your autonomy, then I recommend you sign up for three years and 'try on' military service. As has already been pointed out, you will be recruited at the rank of O-3 (Captain in Army, AF, and Marines; Lieutenant in Navy or CG), or at least O-2 (First Lt or Lt Junior Grade) with promotion to O-3 very soon. So the pay isn't bad, and when you add up the various benefits and the joy of military life (IFF you find it so), it is worth a try.
In the USAF I was close to a number of JAGs along the way. Their lot is nowhere near as exciting as that of Harm Rabb in the TV show JAG! But they get to do interesting things, and they transition between the various legal
specialties (prosecutor, defense, int'l law, mil law, contract
law...) as they desire when they negotiate their assignments along the way. So they're never stuck with the same kind of job too long.
Not to get too personal, but how old are you? How long have you been out of law school
? How physically fit are you? All these are issues to take into account when considering the military.
All the best and good luck with your decision! If you have any additional questions, I'll watch this thread...or you can PM me.