If we, as a human race, actually did manage to colonize other worlds, I doubt the "Navy structure" would be that involved. Granted, you'd still need ships with a captain and crew to run it. Do we need large battleships? Of course not; we're not out in space fighting bad guys who have their own battleships.
I don't see why you're focused so much on what we would do in the real world, where there is almost 100% no chance of us running to Klingons or Cylons or whatever. These stories are FICTION. And if a bad guy has a big spaceship that he's using to try to kill you, what exactly do you plan to do to defend yourself if not use your own spaceships?
I have seen no evidence in scifi lately of the military colonizing other worlds.
I don't see why you're focused so much on what we would do in the real world, where there is almost 100% no chance of us running to Klingons or Cylons or whatever. These stories are FICTION. And if a bad guy has a big spaceship that he's using to try to kill you, what exactly do you plan to do to defend yourself if not use your own spaceships?
I have seen no evidence in scifi lately of the military colonizing other worlds.