U.S. Army Soldiers with 1st Battalion, 509th Infantry Regiment (Airborne) act as an opposing force during a decisive action training environment exercise at the Joint Readiness Training Center in Fort Polk, La., April 25, 2014. Paratroopers with 1st Battalion, 509th Infantry Regiment (A) provide near-peer military, insurgent and criminal opposing forces at the JRTC. (Photo by Staff Sgt. Christopher Klutts, 20th Public Affairs Detachment)