For extraordinary heroism in connection with military operations involving conflict with an armed hostile force in the Republic of Vietnam: First Lieutenant Walker distinguished himself by exceptionally valorous action on 17 March 1969 while second in command of a volunteer night raiding team operating in Dinh Tuong Province. Upon landing, the twelve man team was pinned down by hostile machine gun fire which immediately killed the team leader and the radio-telephone operator. Assuming command, Lieutenant Walker led the men away from the grazing fire to safety. Then, as the element approached the target, a known Viet Cong assembly area, a hail of enemy bullets burst from twin bunker fortifications. While his men fired upon the enemy, Lieutenant Walker crawled forward and destroyed the emplacements with two hand grenades. Once routed, the insurgents, combined with enemy reinforcements, managed to surround the team. A fierce battle ensued, during which the command-and-control helicopter arrived and established a link with the imperiled team. With aid from gun ships, half the team succeeded in breaking free from the encircled enemy and laid suppressive fire while the remainder of the team escaped to join them. The consolidated element quickly formed a circular defensive perimeter. Seeing at this time that the Viet Cong were about to claim the remains of the two soldiers killed in the initial attack, Lieutenant Walker directed his men to drive the enemy away while he crawled outside the perimeter to save both bodies, as well as their equipment. After he returned to the perimeter, the raiding team valiantly repulsed a final assault by two enemy squads. Lieutenant Walker personally stopped three assailants who charged within hand grenade range. When the team moved out to rendezvous with the extraction helicopter, he volunteered to act as the rear security guard. Several times his marksmanship foiled attempts to cut the team off. While finally being evacuated, he continued to engage the enemy with deadly accuracy as the helicopter lifted to safety. First Lieutenant Walker's extraordinary heroism and devotion to duty were in keeping with the highest traditions of the military service and reflect great credit upon himself, his unit and the United States Army.