I just want to know if there is any purpose to having a water navy in a sci fi universe where you don’t really worry about countries on your own planet attacking you, since you’re the only one there.
I just realized that perhaps I should talk about technology, as this could help. The technology is not as advanced as seen in other sci fi series. So, for weapons, all military in the small patch of stars with all these civilizations use the standard array of military planes. Fighters, bombers, attack, cargo, all that. They also have helicopters or something similar, like for example this neighboring alien civilization which our Union of stars tends to have conflict with use ornithopters. Most planes have spaceflight capabilities, and helis can be sent down with the help of cargo aircraft. Some planets use airships, which are kept on the planet. There’s always an army, which can be sent down in large spacecraft. The army uses standard guns, although there are railgun and coilgun artillery and large laser weapons used to cut aircraft apart while they are flying. They use tanks with normal gunpowder fired shells, as well as shell firing artillery. There’s a specialized marine force as well which use high tech multi environment suits. There’s a space force for planetary Defence. Space combat would work like in the expanse, with basically the same weapons. Gatling guns, missiles, railguns, as well as coilguns which aren’t seen in the expanse I don’t think. As for what technology I would think that these naval ships would have. Well, ciws Gatling guns, small cannons, ship to ship missiles, torpedos, aircraft, if it is an aircraft carrier, as well as railguns, coilguns, and lasers. I also imagine there would be stealth submarines.