While I was at OCS, I learned that academy and ROTC guys can only go URL under normal circumstances. I grew up around the AF, where anyone could go into pretty much any job out of the academy or ROTC, and gather from having read "Absolutely American" that the same is true for the Army. I was curious as to why the Navy has this system when it appears that other branches do not.
There are a couple of reasons the Navy does this, I am going to hazard a guess that the main one being we have fewer 'support' officers than the USAF and the Army and many of the 'support' officers we do have are directly accessed into their specialized communities like Supply and Seabees. We are a 'leaner' organization than the USAF and Army for several reasons; the Army needs to have a large and diverse set of officers for the myriad of functions it has to perform from chemical warfare (Chemical Corps) to enormous logistical
responsibilities (three different branches to include Quartermaster, Ordnance and Transportation Corps') and even veterinary services (to include food inspection) the other services don't do on the same scale or even at all. The USAF has some of the same but also a bit of 'bloat' when it comes to their officer corps if you ask me, they have everyone from finance officers that handle stuff our enlisted specialists do and even have MWR officers who run the base gyms and other MWR functions. They also do have a considerable number of specialist officers as well to include space operations folks and specialist engineers in stuff like nuclear and satellite design that the Navy has only on a very small scale.
Another reason is the one Gatordev mentioned, if some of the people didn't get experience first in a 'warfare' specialty then they could spend most of their career out of the loop on what the 'real' Navy actually does for a living. I have seen folks like this across all services, mostly in the USAF though, and it is usually detrimental when an O-5 or O-6 is placed in a position of authority when they have little to no 'operational' experience.
It's actually relatively new. They changed the policy at some point very early on when I was a Mid around '94. It might have even gone hand in hand when they changed everyone's commission to USNR, but I can't remember.
I
remember that as well, as well as how crushed some of my classmates were that they couldn't go straight to Crypto or Intel anymore, but several of my instructors mentioned that they were just returning to 'the way things used to be' just a few years earlier (80's?) that they remembered.