Abstract
Japan is undoubtedly Taiwan’s most important democratic neighbor for its security. Against the backdrop of China’s expansion, incessant confrontations with Japan over sovereignty, and escalating Taiwan-China tensions across the Taiwan Strait, Japan’s defense buildup has assumed significant strategic significance for Taiwan's security. Defense buildup results from perception of threats within the security environment. This paper examines Japan’s threat perception and defense buildup during the Ishiba administration, including defense expenditures, the designated seven defense capabilities enhancements, the prioritized strengthening of Japan’s Southwest Islands defense, and the Japan’s alliance with US and cooperation with other nations. This paper argues that the Japanese government under Ishiba's administration has continued strengthening Japan’s defense, particularly in the Southwest Islands, which are geographically closer to China than other areas of Japan. However, Tokyo faces two conflicting forces on the road to defense buildup: international expectations that Japan should shoulder greater security responsibilities, and a small but vocal domestic opposition. Arguably, the Liberal Democratic Party will continue to wield the greatest influence in Japanese politics. Nevertheless, reconciling these two conflicting forces will undoubtedly be a challenge in the Post-Ishiba Era.