North Korea plots to take away a part of Japan and they do this very, very intelligently. Japan can't do nothing against this, because whatever it does, it would look and feel worse. In the end, it is people from outside Japans society that finish off the intruders.

The fields of tension here are different cultures of Asia, poor-rich, city vs. land, inside society or outside and so on. It's really more than just a military thriller or something.