if nuclear exchange will make the kimchee spicier, I don't really see the harm in it...

In all seriousness though...
Does anyone actually think threatening a nuclear attack by NK is going to have any bearing on US policy towards NK in a way that benefits NK?
No, I didn't think so.
Concessions from the USA will not be given to NK under threat of any attack (conventional, chemical, nuclear, or even "we'll give the stuff to terrorists.") That's plain and clear.
I have a bad feeling this is going to come down to the USA perceiving this to be sabre rattling and a bluff and call NK out on it (either literally, or figuratively by embargos, blockades, etc.) Then we'll see if NK was just jerking our chain or if they really want Korean War II. If they do, I wonder when the 250,000 Chinese regulars come streaming across the China-NK border if they'll be shooting at NK's army or ours.