Private First Class Hackenberg was a Light Weapons Infantryman with Company F, 2nd Battalion, 35th Infantry Regiment, 25th Infantry Division. He was taken Prisoner of War while fighting the enemy in South Korea on April 25, 1951 and died while a prisoner on September 9, 1951. His remains were not recovered at the time. In 2017, Hackenberg’s remains were identified by the Defense POW/MIA Accounting Agency. His name is permanently engraved in the Korean War “Courts of the Missing” at the Honolulu memorial.