First Lieutenant Arnold was a member of the 5th Cavalry Regiment, 1st Cavalry Division. He was Killed in Action while attacking Hill 222 in North Korea during “Operation Commando” on October 3, 1951. First Lieutenant Arnold was awarded the Purple Heart, the Combat Infantryman’s Badge, the Korean Service Medal, the United Nations Service Medal, the National Defense Service Medal, the Korean Presidential Unit Citation and the Republic of Korea War Service Medal.