The North Korean are always threatening their neighbors (and pretty much anybody else) with a "nuclear sea of fire".
It reminded me of an old picture I had seen of the USS Agerholm (DD-826) (fondly known as the "Saggy Aggy") when she shot a nuclear depth charge using an ASROC (anti-submarine rocket). Thanks to the miracle of the internet, I was able to track down that photo:
Man, that makes a big hole in the ocean!
More photos at this site. Scroll down to find them.