Im gonna have to jump in on this one also. I have been in 16 years now, and the happiest day of my life will be the day i retire. I have worked extensively with all 4 branches, and the Coast Guard, both stateside and overseas. My wife and I are both active duty. She spend her entire career in intel, and mine has been spread amongst 6 career fields, but mostly in AFSOC/SOCOM world.
If you were my child, asking me the same question, I honestly couldn't recommend it in today's military. It has changed so much in the last 16 years that its just not worth it to me. Don't mistake what I am saying as regret; I wouldn't take back a second of my career. It's just that the political BS is overwhelming now. The majority of our time is spent in "Sensitivity training", "diversity training", "resiliency training" and other BS. Every time someone screws up, you get to go thru the training all over again. I have been thru homosexual awareness training, religious sensitivity training, and diversity training till I'm sick to death of it.
The idea people have had of the military no longer exists. In the old days, I could chew some troops ass for screwing up, and that would be it. Now, you have to be careful. Is that troop a different race/sex/religion than you? Have you documented previous attempts to inform the individual that their conduct was unacceptable? Does that individual possibly have a religious/racial/gender related/ or learning disability preventing them from understanding what you have told them? Have you been thru the proper sexual orientation/gender/religious/learning disability sensitivity training to be able to properly address the issue to the individual in a way they will understand? Things like this are an everyday occurrence. We nove have a generation of kids that have never held a job, never been disciplined in their entire lives, the "no child left behind" syndrome, who think the world owes them something. Add this to the fact that our current leadership has been constantly downsizing us, forcing the older, more experienced NCOs out (some at 18-19 years), increasing deployment time, decreasing time spent at home, whittling away at our benefits, and you have a disaster that is today's military. Oh, and did I mention that all the decisions affecting your life are made by people who have never been in the military? Now they are reducing our retirement! What other job in the world asks you to do what the military does, promises you that if you do that, it will give you these sets of benefits, then takes them away while you are doing it?
The other guys on here also hit the nail on the head. All these things have created a "me first" mentality. Leadership is worried about their evals and getting promoted. Screw the people under you. This, combined with the things listed above, have trickled down into the NCO tiers. We have been so beat down and had our hands tied with bureaucracy that you just do what you have to to survive. You see guy who test well, or are friends with the right people, or volunteer for the right things fly thru the ranks, even though they know nothing about their jobs. It will beat even the best intentions out of you eventually.
As for the marriage thing the Op asked about.....
There is a reason the military has a much higher divorce rate than the civillian population. Everyone I know who has been in for awhile has been divorced at least once. Some of the reasons are:
Being gone all the time, and I mean ALL the time, is a huge factor. Have you been away from your wife for a year or more before? You will.
When you are home, downsizing means you are always at work. 12-16 hour days/nights is not uncommon. You are on duty 24/7 and it would do you well to remember that early in your career.
Uncertain work schedules. You just worked 8 hours and are on you way home when you are called back in. You are needed to work a 12 hour night shift. Sorry! (and yes they CAN and WILL do that).
The fact that you can't really make plans with any certainty also doesn't help.
But, its not just the mission that causes stress on a marriage. Like it was mentioned before, there are a LOT of backstabbing individuals in the military. It's a very gung-ho, macho lifestyle for some. Is your wife attractive? If so, there are a lot of other guys in your unit that will think so too. They may not hit on her to your face, but wait till you deploy and see how much "help" shows up at her door. Its a huge game in the military. I have never seen some much adultery and sexual deviantry in my life as I have in the military. EVERYONE is screwing around with everyone! (That young female you just chewed out for being 2 hours late for work, well, she secretly is screwing your boss type of thing. )
Now, onto the MOS thing you spoke about. I can only speak for the AF when it comes to this, but every branch makes ass backwards decisions. In the AF, if you are selected to be an officer and meet their very strict requirements and have a degree they happen to want at the time, you are sent to OCS. You cannot choose your job and your degree has little to no influence on your final job assignment. (I know guys who came in with aerospace degrees and an active pilots license who manage the chow hall). You must remember this saying "In the best intrest of the Air Force". Everything in your life will revolve around this saying. Also remember, when you join the military, you give up the rights you had as a civillian. If you can live with all these things, by all means, go for it. I can be an amazingly rewarding job.....But don't say I didn't warn you!