Taiwanese President William Lai is preparing the island for emergencies amid rising tensions with China.I-Hwa Cheng/AFP/Getty ImagesTaiwan has held its first tabletop war game amid rising tensions with China.The exercise simulates military escalation and involves government and civil groups.Taiwan aims to train 50,000 volunteers for emergencies amid China's military drills.Taiwan's Presidential Office held its first-ever tabletop war games on Thursday in a sign of heightened tensions with Beijing.The exercise simulates a military escalation with China, which claims Taiwan as its territory.