I’d echo what Sunrazor and What Exit? have already said, which is consistent with all I’ve read elsewhere. I considered joining the Navy several times in my youth but never did, and even mulled over applying to Annapolis out of high school. I did neither, and still regret it now and then. Come back to the thread, please, Really Not That Bright, and tell us more about what you’re thinking. If you decide to join the U.S. military and seek citizenship, we thank you and we welcome you.
Really Not All That Bright, Wikipedia has a pretty decent overview of the Coast Guard. If you have any questions, let me know.
Joining the Navy doesn’t mean you have to bob around on the waves. The Navy Seabees are the construction force. In 23 years, I never set foot on a boat. The Navy also has its air wing, but at some point you would probably end up on an aircraft carrier. They have pretty decent shore stations, though. Clearances can be a problem in many ratings, such as CT (communications tech) and in the nuclear navy group.
And here are the jobs a non-citizen can get in the U.S.A.F.
BTW, **REALLY NOT THAT BRIGHT, the President (love him or hate him) has waived the three year condition for applying for citizenship if you are serving in the Army, Navy, Air Force, Marines, or Coast Gaurd.
Sorry, guys. My router blew up yesterday…
Anyway, I’m very grateful for all the replies so far, and it looks like I need to clear a few things up.
The three-year citizenship rule isn’t a problem, as I’ve been a (lawful) permanent resident of sunny Florida since 1996. I WILL be applying for citizenship regardless of whether or not I enlist.
I have neither debts nor a family (well, at least not in the sense of a wife and kids). I do have an angry girlfriend.
The limits on what you can do as a non-citizen are a lot more extensive than I thought 
I’m not so sure I want to do something I don’t like for four years for a chance to do something I like. Keep the advice coming though, please!
Is she angry because you’re considering joining the U.S. military, if I may ask?
And have you considered joining the Royal Navy, as someone asked upthread? I’ll gladly quote Churchill for you, if so.
Is this a new thing (well, not new but within the last 10 yrs)? I enlisted almost ten years ago and I know two guys that ended up being SP’s because their recruiters convinced them to go in Open General.
Yes. And no.
I’m pretty sure that a military obligation to another sovereign government disqualifies you from US citizenship.
And the services pay horribly in Britain, at least last time I looked.
Oh dear.
I’d completely forgotten there used to be a Naval Training Center here in Orlando until I read that.
It’s called Baldwin Park now and it’s a housing community for yuppies.
I spent six months there going to school there. We spent most of our off-duty time over in Castleberry, though.
I don’t think there is going to be much of a problem with your citizenship. It’s not like you come from a family of Afghan warlords. A friend of my step-daughter-to-be just got back from a two-year tour in London (she’s USAF officer), and she worked closely with the RAF.
Shows what you know. 
(Bolding mine)
Ummm… you might not want to show this thread to any recruiters, then.