Ginga Rengou Nippon: Age after

Year 201X-A giant spaceship flew over Japan. Aliens with extraordinarily advanced scientific powers are for some reason interested only in Japan and no other countries on earth, and let the spacecraft wait over Sagami Bay. In the midst of this unprecedented situation that undermines the world's power balance, powerhouse nations, including the United States and China, are upset. MC is appointed as a negotiator and plans a large-scale operation to establish diplomatic relations with the aliens.