Good idea:
A sea mine is a promise of tragedy in the future. Built for the immediate demands of a naval conflict, deployed for some once-pressing strategic end, and now left in place for decades, sea mines are an enduring risk. Clearing the sea from the dangerous refuse of the past can be a high-stakes proposition. Why not, then, let robots do it?
It won't be long before sea mines are themselves moving swarms that slowly travel away from such robotic hunter killers and can move to more target-rich environments.
Perhaps minefields will have defensive escort mines that attack the minesweeping swarm.
This capability will eventually be lethal.
I note a similar prediction for land forces. And there is an air defense version I have advocated, too.