They can threaten South Korea if they want, we have a nuclear contingency in place for N Korea and they know it. Any chem or nuke on S Korea results in lots of barren unliveable earth just north of the DMZ.
I have noticed that when ill kim thinks he is being ignored ,and by the US ,he officially has been, he throws a temper tantrum. His missles are a joke. He is a joke. His bombs? ehh. whatever, kim baby.
North Korea is China's red headed step child....
We should do NADA!
Unless we feel that we are short on "Boat People"....
The scourge of Communism has been replaced by the scourge of Islamic carp....
If it ain't one thing it is something else......
North Korea will live or die by it's own merit & be assimilated........JK