The Japanese term gokan is used here in the sense of an escort, explaining why ships of different sizes share a designation commonly translated as destroyer. The Japan Maritime Self-Defense Force screens the home islands and sea lines of communication, with an additional role supporting allies. This gives the escort fleet a strategic purpose beyond protecting an individual formation. Japan has limited territorial depth, so keeping combat out at sea is central to this interpretation of its naval mission.
Chapter · 5:10-6:58
Japan's escort terminology explains its maritime screening strategy
The gokan designation places Japan's warships within a force that screens the home islands, trade routes, and allied operations.