alt Hacker NewsA drone of this type and a cruise missile are literally the same type of thing, they just occupy different points on the capability spectrum.
You assert "plenty of defenses against torpedoes don't work against [UUV]". Based on what? What is this hypothetical property of a UUV that is superior to a torpedo?
A UUV with sufficient range and warhead is going to be big and heavy. Long-range torpedos weigh 2 tons each for a good reason. Calling something a "drone" or "UUV" does not imbue it with magic physics. It still has to cross some long span of water with enough speed and a large enough warhead and a guidance package capable of finding the target.
What kind of vessel are you going to use to bring these UUV within range of the target? 20 torpedos would be almost the entire magazine depth of an attack submarine. Surface combat ships carry even fewer.
You seem to be ignoring all evidence from how modern naval systems actually work when discussing your hypothetical UUVs.
> A drone of this type and a cruise missile are literally the same type of thing, they just occupy different points on the capability spectrum.
You have a "this type" in your mind. I do not. Even then you're wrong. A drone can loiter and is thus not "literally the same type of thing" as a cruise missile or torpedo.
> What is this hypothetical property of a UUV that is superior to a torpedo? [...] It still has to cross some long span of water with enough speed and a large enough warhead and a guidance package capable of finding the target.
The huge advantage of drones (besides relatively low cost) is not how they cover the distance, but their flexibility in getting to the target, striking with high precision. An underwater drone can technically even circle the target before striking it at its weakest point (although this isn't going to work well if the target is at full speed).
> What kind of vessel are you going to use to bring these UUV within range of the target?
Bigger UUVs. Note that 'within range of the target' is also much higher for UUVs versus torpedoes, easily 160km for UUVs. Note that ambushes with these UUVs may also be an option, if they can loiter or just lie on the sea floor.