For China, whose President Xi Jinping is already taking an increasingly muscular approach to claims in the East and South China seas, the question of Taiwan trumps any other of its territorial assertions in terms of sensitivity and importance.

After eight years of calm in what had been one of Asia's powder kegs, the landslide election of an independence-leaning opposition leader, President-elect Tsai Ing-wen, has thrust Taiwan back into the spotlight as one of the region's most sensitive security issues.

Defeated Kuomintang forces fled to Taiwan at the end of the Chinese civil war in 1949. China claims Taiwan as its sacred territory, is estimated by Taiwan to aim hundreds of missiles at the island over a narrow stretch of water and has never renounced the use of force to bring it under its control.