Well, guess I should weigh in here. I recently retired after 30 years of military service (My wife is also a 20 year veteran). Two years in the Army as a draftee - one in the U.S. and one on the ground in Vietnam. Four years in the Army Reserve and finally 24 years in the Navy first as a F-4 Pilot then as an Intelligence Officer. Medically cut from flying and moved to Intelligence.
In many ways joining the military service is like joining a college fraternity - in order to get the most from it and enjoy what you are doing you must find a service (and a job) that is compatible with your personality and interests. If you don't you'll never be happy. I counted down every day in the Army and loved the Navy. It was better for me.
Marines: If you want family. If you want a close net group that works and plays hard and together. If you want to know you'll be looked after by your seniors. The Marines expect and demand a lot from their people. Truly "can do." IMO the overall best of the best and their pride shows it.
Navy: If you respond to thinking on your feet to get the job done, regardless of the rules. Make it happen. Self starter. Able to see what needs to be done and then does it - w/out being told. If you can deal with that and working until the job is done, regardless of the hours, before your time off, this is best for you.
Air Force: If you really want the training to work in the corporate world upon finishing your enlistment here it is. A real 9 to 5 organization. Very difficult to rise above your job description.
Army: I won't comment. I'll let others. It's just not me at all, but I'm glad as hell they are there and I've got several friends I still stay in touch with after 35 years.
Coast Guard: if you are considered mature for your age and are able to accept a lot of responsibility this is your place. Because they fall under the Dept of Transportation, not DOD, their promotions are much slower. Different rules.
Keep in mind there are good people in all the services...and there are people you wouldn't give the time of day - some are your bosses and some work for you. The same applies for jobs. There are jobs you hate to leave when your tour is up, and jobs you can't wait to get out of. It's just the way it is.
I can only speak for the Navy and Air Force in the matter of opportunity, but the educational opportunities are limitless...IF... you want to seek them out and go for it. They won't come to you.
Some jobs are perfect for one person others are not. For example, the Navy has difficulty keeping Gas Turbine Tech's. As a result the promotion and bonus multipliers are jaw-dropping. These are the guys getting the BIG reenlistment bonuses. Same for the dental techs that make crowns. Can't keep them. On the other hand the Post Office is manned at over 100% because everyone wants to work for the postal service as soon as they leave the service. As a result promotions are slow.
I urge you to take a full battery of interest and aptitude tests prior to talking to a recruiter. Then ask about jobs which meet your qualifications. You'll be happier in the long run. And for many jobs you can enlist for that job. Remember however, normally enlisting for a specific job requires you enlist for a longer period of time. Navy Nuclear Techs go to school for two years and spend four years in the fleet - 6 years. Be flexible. If you are not, you'll have a tough time regardless of the service you choose.
A very close friend recently retired after 30 years as a Navy Seal Officer. He's still working in the field, now as a civilian. He speaks very highly of the Air Force and Marine Spec Ops. He doesn't care for the Army's MISSION for their spec ops people - SEALs do a lot of Intelligence gathering, and very specific tasks, some not so nice. The Army gets close with the locals and works with them. Great if that's what you want to do. Not disparaging the Army's spec ops, it's like I said about the job. It has to be good for you.
...BUT remember for ANY spec ops in any service you HAVE TO WANT IT or you will never get through training. AND, at least with the Navy's spec ops folks, once finished your life is the SEALS. BUDS is 23 weeks (it's typical for only 23-25 to graduate from a starting class of 140-150) then specific training and once assigned to a SEAL Team, routine deployments are six months followed by a year at home. Of that year 10 months are in training and 6-8 months of that are away from home. Then it's back on deployment. Like I said you have to want it.
The person that indicated you should finish college first and go in as an officer is correct, but keep in mind the standards are currently very high. Civilian jobs are difficult now so people look to the services. At the same time the services are cutting back so there are fewer jobs. Supply and demand.
Now just in case those of you reading this think I am not qualified to talk about other services, 10 of my Navy years were in Join Commands. I have written many Evals (Enlisted) and Fitness Reports (Officers) on people in ALL services. I have worked for seniors from all services. In fact if you read the papers or listen to the news, I was the Executive Assistant for the current retired AF 3-star being considered for the National Intelligence Director. I know him well. He's a VERY GOOD man and I have the utmost respect for him. I'm not a name dropper, just trying to let you know my qualifications to speak about other services. If you have specific questions please ask. I'm very proud of my military background and once you serve you will also.
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