 In 1971 the U.S. authorized the ARVN to carry out an offensive operation aimed at cutting the Ho Chi Minh Trail in southeastern Laos.Besides attacking the PAVN logistical system (which would buy time for the U.S. withdrawal) the incursion would be a significant test of Vietnamization.Backed by U.S. air and artillery support (American troops were forbidden to enter Laos), the ARVN moved across the border along Route 9, utilizing the abandoned Marine outpost of Khe Sanh as a jumping-off point.