Japan is considering expanding an Okinawa-based ground force unit to defend remote southwestern islands and prepare for a contingency involving Taiwan in the face of China's increasing assertiveness, a government source said Saturday.In a move that could further heighten tensions with China, the Defense Ministry plans to double the number of infantry regiments under the Ground Self-Defense Force's 15th Brigade to two, as well as upgrade its highest rank from major general to general, the source said.The planned changes, to be included in one of the three key security documents the governmen…READ FULL ARTICLE