Yes, to me, Japan's decision to deploy missiles on Ishigaki Island is a significant development in the ongoing geopolitical tensions in the Asia-Pacific region.
The island's strategic location, close to Taiwan and the Diaoyu Islands, makes it a crucial point of control in the event of a conflict. The deployment of missiles, which could target both naval and aerial threats, would significantly enhance Japan's defensive capabilities in the region.
Note that China has strongly opposed Japan's military buildup in the Ryukyu Islands, which it considers to be a violation of its sovereignty. The deployment of missiles on Ishigaki Island is likely to further strain relations between the two countries.