200304-N-RU810-1060 GULF OF THAILAND (March 4, 2020) Chief Hospital Corpsman Peter Tan, from La Mirada, Calif., assigned to the San Antonio-class amphibious transport dock USS Green Bay (LPD 20), simulates clearing the airway of a casualty during a mass casualty drill in support of Exercise Cobra Gold 2020, March 4, 2020. America Expeditionary Strike Group-31st Marine Expeditionary Unit team are participating in Exercise Cobra Gold 2020, the largest theater security cooperation in the Indo-Pacific region and an integral part of the U.S. commitment to strengthen engagement in the region. (U.S. Navy photo by Mass Communication Specialist 3rd Class Vincent E. Zline/Released)