You do realize that underwater drones exist and have been successfully used against Russian ships, right?
In the navy they call long-range underwater drones a "torpedo". It has been assumed to be a primary threat against ships for a century. Modern navies have many systems purpose-built to deal with that threat.
alt Hacker News
In the navy they call long-range underwater drones a "torpedo". It has been assumed to be a primary threat against ships for a century. Modern navies have many systems purpose-built to deal with that threat.