The Wormhole wrote:
For a while, Canada's military used the same ranks in all its branches. Yes, that means Canada's Navy used Army ranks. Colonels commanded boats, Generals commanded fleets.
This is no longer the way, the Canadian Navy is using tradition naval ranks these days, although some of the enlisted men still use army ranks. I know a guy in the Canadian Navy who hold the rank Corporal. My point is that there are real world precedents for army ranks to be used in the navy.
But by the same analogy, the Canadian Forces' brief use of the same rank system in all of its commands didn't last very long, did it? They went back to the old systems fairly quickly after unification. Who's to say the same thing didn't happen in Starfleet? They could have a single, unified military command, like Canada, and yet have unique rank systems.