This year’s annual Balikatan joint military exercises between the Philippines and the United States (April 22-May 10) broke much new ground. So did China’s response to it. The exercise areas and the arms deployed showed the linkage of South China Sea and Taiwan Strait hotspots. A surge in Chinese vessel presence in Manila’s western exclusive economic zone and another violent sea incident over a contested reef expose Beijing’s defiance amid the alliance’s show of force. The display of strength and the reaction to it escalated tensions in choppy waters and raised questions about the drill’s deterrent value. The symbolism and messages show how parties are digging in, accepting more risk and shrinking the space for diplomacy.