MD (or DO if that is the route you'd prefer)decision matrix:
1) I want to be a doctor --> go to college and then onto med school
2) I want to be an Army Doctor --> go to college, consider taking ROTC the first two years to decide/confirm your choice but don't contract or see about internships with Army medicine, complete med school, then see the recruiter about a direct commission (also works well for Vets and Dentist).
3) I want to be an Army Officer, with the best odds of having it funded and shortest timeline to become a doctor --> ROTC (sheer numbers of ROTC vs USMA = more spots, and if you don't make it, your ADSO is 4 yrs vs USMA 5 which means you can get back to med school sooner on your GI Bill, or the option of serving in the Guard or Reserve = even sooner to start med school)
4) I want to be an active duty Army Officer and it would be great to do it as a doctor, but the doctor part can wait --> USMA
It's a lot to think about at this point but it really comes down to you mapping out your goals not just for college, but as mentioned above, the next 20 years. I know doctors across the full spectrum from those that went route 1 and then after 9/11 came on active duty as COLs (were like the head of major medical center ERs), to the direct commission CPTs (majority of Army doctors), to the USMA/ROTC straight to med school, to the Infantry Officer who after serving a number of years AD went back to med school and then came back as an Army doctor.
Another thing to consider if you want to be a doctor is do you have a specialty in mind? If you are particular, you have to determine how much the Army needs that specialty. Some they will pay significantly for but don't need many; general physicians are needed in greater quantity, but are easier to find/recruit. It all goes into that plan to realize what you want in life and how realize it.