Last week, a CNN crew flying onboard a US Navy patrol plane above the South China Sea recorded China’s military ordering the navy jet to exit a “military alert zone,” shedding light on Beijing’s ongoing attempts to exert administrative control over international airspace and waters. Just two weeks earlier, Philippine’s Defense Secretary publicly expressed concern that Beijing was taking steps to establish an Air Defense Identification Zone (ADIZ) over the contested South China Sea. Chinese officials haven’t ruled out the possibility of establishing a new zone, and new military facilities in the South China Sea could streamline Beijing’s ADIZ enforcement efforts. Establishment of such a zone would undoubtedly heighten diplomatic tensions between Beijing and other South China Sea actors and raise the likelihood of confrontations between military aircraft operating in the region.