Opposing these government forces in the early fall of 1962 were Viet Cong forces of formidable strength. Four interprovincial battalions (main force), four interprovincial companies, five provincial companies, 18 district companies, and three district platoons were known to be operating within the boundaries of I Corps. Together, these units totalled an estimated 4,750 men.[6-1] Added to the presence of these known Viet Cong units was the threat posed to I Corps by its proximity to North Vietnam and to the so-called “Ho Chi Minh Trails” located across the Laotian border. The relative position of the northern provinces naturally invited Communist infiltration. In June, for example, the _4th Viet Cong Battalion_, a main force unit, was infiltrated into Quang Nam Province from sanctuaries in Laos. By September MACV intelligence estimates reported one North Vietnamese (PAVN) infantry division, two independent PAVN infantry regiments, and an artillery regiment poised in areas of Laos adjacent to the I Corps border. “These units,” the U.S. report warned, “... could be committed anywhere in I Corps or [the] northern part of II Corps 20 days after starting movement.”[6-2] While the government’s nationwide strategy focused on clearing and holding the populated areas, the physiographic configuration of I Corps (as well as II Corps to the south) demanded that offensive operations be conducted in the mountains adjacent to the coastal plains against Viet Cong base areas. Since the arrival of the U.S. Army helicopter company at Da Nang early in the year, General Don had shown an increasing tendency to mount battalion and regimental heliborne assaults deep into the western mountains. Capitalizing on the mobility which the American helicopters afforded, the ARVN command had hoped to disrupt remote Communist base areas inside the international border. Still, heliborne offensives into western I Corps were often hampered by bad weather, particularly during the monsoon season. Another facet of the government effort to deny the enemy unrestricted access to the mountains was a system characterized by a network of small, relatively isolated outposts. In late 1961, at the urging of U.S. officials in Saigon, the Diem government had launched a program whose ultimate objective was similar to that of the Strategic Hamlet Program. First, U.S. Army Special Forces teams entered remote Montagnard villages located in the Annamite Chain and built small fortified camps. This accomplished, the Americans initiated pacification activities with the hope of securing the allegiance of the traditionally independent Montagnard tribesmen.