> Similarly, it is easy to imagine a swarm of small underwater drones detecting, tracking and trailing nuclear submarines.

Those are called torpedoes.

It’s way cheaper to build a drone that doesn’t need to travel quickly or carry huge amount high explosives.

How is a slow, lightly armed drone going to damage a nuclear submarine that can both outrun and outdive it?

	▲	Retric 8 hours ago \| parent [-]
		The drone’s goal is to locate it, you’d then send something else to destroy it if you’re in an actual war. America uses surface buoy’s to similar effect, going underwater would allow drones to be harder to detect. https://idstch.com/military/navy/navy-researching-new-buoy-t... Of note you don’t necessarily need to be able to track a sub everywhere, an invisible underwater “fence” may be good enough.