These are no ordinary times in East Asia. With tensions rising from conflicting territorial claims in the East China and South China seas, the region increasingly resembles a 21st-century maritime redux of the Balkans a century ago -- a tinderbox on water. Nationalist sentiment is surging across the region, reducing the domestic political space for less confrontational approaches. Relations between China and Japan have now fallen to their lowest ebb since diplomatic normalization in 1972, significantly reducing bilateral trade and investment volumes and causing regional governments to monitor developments with growing alarm. Relations between China and Vietnam, and between China and the Philippines, have also deteriorated significantly, while key regional institutions such as the Association of Southeast Asian Nations (ASEAN) have become increasingly polarized. In security terms, the region is more brittle than at any time since the fall of Saigon in 1975.