Japan is accelerating its defense buildup on its southwestern islands amid rising geopolitical tensions in the Taiwan Strait and the wider Indo-Pacific region, a Japanese daily reported.The Japanese Ministry of Defense plans to upgrade the Japan Ground Self-Defense Force’s 15th Brigade, based in Nah. Add TT as Preferred Source Japan is accelerating its defense buildup on its southwestern islands amid rising geopolitical tensions in the Taiwan Strait and the wider Indo-Pacific region.