Personally, I'm not climbing into the bunker yet. Those North Koreans play a different brand of rock and roll and this just seems to be the same bluster, higher volume.
But I find it interesting that Russia has publicly declared a nuclear warning. Not surprised, I guess though, because it could in the end benefit Russia to ratchet up global fears. One obvious result might be a bit higher oil prices. We won't go into the possibility of certain commisars and siloviki actually hoping for tensions to erupt into an expanding hot war.
Russia fears Korea conflict could go nuclear - Ifax