In your case, joining the military to be a diver is just a "cop-out". Dude, you are in the middle of the most important thing you can do in your life! Finish the stupid college degree. It doesn't matter what you get it in, it's the fact that you finished and you have received the education that will help you think differently than the common high school drop-out.
You want excitement while you finish up college, than go get a summer position with the U.S. Forest Service or the California Department of Forestry and Fire Protection and chase brush fires for a couple of sumers. You'll get the same physical challange, the mortal danger and it's all over at the end of the season, or start of the school year, which ever comes first.
You want to be a commercial diver, do like Steve Barsky, go to Santa Barbara City College in Santa Barbara and attaned the Marine Technology program, now while your still young. Companies don't hire old commercial divers unless they have lots of experience, a solid reputation as a get it done guy and some sort of special skill. Then drive to Morgan City, LA with a stack of resumes and knock on the doors of all the commercial diving companies down there. You will be competing with thousands of commercial diving school graduates that only have high school deplomas, or less for a job that pays $10 to $12 an hour, working 12 hour shifts, 7 days a week and with no expected holiday or day off. The two months on three off died when commercial diving companies started putting their dive spreads on work boats and motoring from job to job.
Last of all, IF you want to be a military diver, you need to be committed. It's a way of life, not a change of career or different choise of school. Right now military folk are dying just trying to do their job. Don't think you might spend some time in Afganistan, or Iraq. The Army needs security forces and they are using anyone who can carry a rifle to sit shot-gun on convoys. YOU WILL GO TO THE THEATER at some time if you go military (Coast Guard is the exception and they have very, very few divers). Also the commitment is eight (8) years, not two or three. You will be told you do four active. What the recruter will forget to explain is you are still on the hook for four more after that as an inactive reserve which is nothing more than a guy that will get a phone call to pack up his sea bag of uniforms and report for 15 more months in country after you have been out for a couple of months. Go to
Benefiting the US Army, US Navy, US Air Force, Marine Corps, Coast Guard - Military.com and do some more research before you make that decision.