 To threaten this flow of supplies, the Marine Corps established a combat base on the South Vietnamese side of the Laotian frontier, near the village of Khe Sanh.The U.S. used the base as a border surveillance position overlooking Route 9, the only east–west road that crossed the border in the province.Westmoreland also hoped to use the base as a jump-off point for any future incursion against the Trail system in Laos.