system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is it that in Science Fiction, Military Space-faring vessels are almost always controlled by the Navy?

Space *Marines*, Ship-based personel having naval rankings, Nautical terms used both onboard and when commanding/piloting a spaceship etc. 

Whether it's explicitly said or not, the Navy (or a space variant of) always seems to be the branch of Earth's military forces which control our future space-faring vessels. 

Why did this become a trend and is there any real-life reasoning for why this might be the case in the future? Would it not make more sense for the Air Force to have jurisdiction over militarized space-faring vessels as space is just an expansion of their existing domain?
gpt
Because the Navy is the branch of military that is most often associated with travel, and ship, and such.

Not to mention naval terms are often used because the other branches don't really have terms for such large modes of transportation.

Most likely in the future it would not be any current branch in charge of spacecraft, warfare or travel, it would be some new branch. The Navy is just used because when it comes to navigation, operating ships and fighting the kind of battles that you would see in space, as of right now, the Navy is the best we can think. The Airforce would be good for dogfights, the army would be great for assaults, but when it comes to ship to ship manoeuvres, the Navy is currently the best.