We Were Soldiers Once...and Young: la Drang - The Battle That Changed the War in Vietnam is a 1992 book by Lt. Gen. Harold G. Moore (Ret.) and war journalist Joseph L. Galloway about the Vietnam War. It focuses on the role of the First and Second Battalions of the 7th Cavalry Regiment in the Battle of the Ia Drang Valley, the United States's first large-unit battle of the Vietnam War; previous engagements involved small units and patrols. It was adapted into the 2002 film We Were Soldiers.