I don't know how true it is, but I remember hearing somewhere that in the RW there is an element of British English v American English based on the full name of the ship in question.
Royal Navy ships are "Name", because they 'belong' to an individual. For example Her Majesty's Ship Queen Elizabeth (the new RN carrier)
US Navy (and Coast Guard) ships are "the Name", because they 'belong' to a collective ie they are "The (United States' Ship) Name. For example the United States' Ship Wasp (the broadly equivalent LHD in US service.
Makes sense to me?