OSAN AIR BASE, Republic of Korea -- Getting their faces in the dirt, Airman practice low-crawling during the Installation Arming and Response course. In this course, Airmen E-1 through E-6 will be taught how to defend against, deny and delay opposing forces. The January and future exercises will use the method to provide defense of the base. (U.S. Air Force photo by 2nd Lt. Kim Schaerdel)