U.S. Army Soldiers from the 3rd Battalion, 13th Field Artillery Regiment, attached to the 2nd Brigade Combat Team, 1st Infantry Division, set up an OE-254 communications system during Decisive Action Rotation 15-06 at the National Training Center, Fort Irwin, Calif., March 25, 2015. Decisive Action Rotations allow units to fully exercise their Mission Essential Task List that supports the Army's core competencies: Wide area security and combined arms maneuver. (U.S. Army photo by Spc. Ashley Marble/Released)