Operation Union II was a military operation that took place in the Vietnam War. It was a search and destroy mission in the Que Son Valley carried out by the 5th Marine Regiment. Launched on May 26, 1967, the operation ended June 5. It was a bloody 10-day battle that resulted in 594 NVA killed and 23 captured, while U.S. casualties were 110 killed and 241 wounded. The Importance of the Que Son Valley in the Vietnam War The Que Son Valley is located along the border of Quang Nam and Quang Tin...