Russia to Deploy Submarine Armed with Nuclear Drone in Pacific (thedefensepost.com)

I've heard that the main job of a nuclear submarine is to tail another nuclear submarine at a polite distance, so every submarine that could make a first strike is observed by a submarine that could make a retaliatory strike. Then again, wouldn't the defensive side be out of range of the attacking country for a second strike? So maybe it's to be able to launch anti-missile missiles...

Scary stuff, but I guess it gives sailors something to do.