A Royal Thai Marine take off his gas mask after going through a decontamination line during chemical, biological, radiological, and nuclear decontamination training at Camp Samaesan, Thailand, Feb. 14, 2012. Marines and sailors from the 31st Marine Expeditionary Unit also participated in the training, the training was part of the multilateral training Exercise Cobra Gold 2012. Cobra Gold 2012 demonstrates the resolve of the U.S. and participating nations to increase interoperability and promote security and peace throughout the Asia-Pacific region. The 31st MEU is the U.S.'s expeditionary force in readiness in the region.