We in the west have long forgotten that North and south Korea have been at war for over 60 years. They have been living under a cease fire agreement since the mid 1950s, but have been and still are at war. It has always been just a matter of time before either country felt strong enough to resume active fighting. Right now both seem to be testing the waters, so to speak, the show of backing down by either side will most likely result in an Invasion attempt.
Sadly if it does come to military might the innocents of both countries will be the people who suffer the most.