U.S. Army Reserve Pfc. Nicholas Rivers, a human resources specialist with the 678th Postal Detachment from Sheffield, Alabama, conducts a simulated ambush on Soldiers attending Postal Warrior 19-2 at Joint Base McGuire-Dix-Lakehurst, New Jersey, Aug. 10 to 30, 2019. Nearly 600 Soldiers from postal platoons across the country are participating in Postal Warrior 19, a training exercise that validates their ability to support Theater Postal Operations. (U.S. Army Reserve photo by Maj. Brandon R. Mace)