Not just drones, but -swarms- of drones. I make that point because its important to differentiate between what could be massive, battleship (or, likely, crusier) sized drones, and collections of very small drones.

There's reasons this makes sense, even in the context of a fight against battleships (please assume similar technical capability, since a WWII Battleship would likely not fair well against a 2020 drone swarm..) A battleship, even a big automated one, has a series of weak points, such as sensors, removal of which can cripple the ship, and a swarm doesn't lose effectiveness at a blast from heavy weaponry...it may get a hole punched through it, and have only a few drones taken out...