It's not just South Korea and its citizens who stand to suffer if the war with the North turns hot. Other nations would be drawn into the conflict. Not only that, nations such as Japan have citizens living in South Korea who would be at risk. What is to be done about them?
With 60,000 Japanese residing in South Korea, the resumption of hostilities between the North and South is not a tangential issue. Should things turn violent, how to quickly evacuate its citizens is a real problem. Perhaps the Americans with our enormous navy could be of assistance, but it's also very likely that those navy ships will be directly involved in the conflict and not able at that time to focus on humanitarian missions.
As a result, Japan has had to prepare for a renewed Korean war from the standpoint of not only defending itself, but in terms of defending its citizens who might be caught up in the hostilities.
More on page two.