Moreover, the allies could not concentrate their efforts everywhere as they had in strategic Binh Dinh. The expanse of the highlands compelled Army operations there to be carried out with economy of force. During 1966 and 1967, the Americans engaged in a constant search for tactical concepts and techniques to maximize their advantages of firepower and mobility and to compensate for the constraints of time, distance, difficult terrain, and an inviolable border. Here the war was fought primarily to prevent the incursion of NVA units into South Vietnam and to erode their combat strength. Cordon and Search operation in support of pacification In the highlands, each side pursued a strategy of military confrontation, seeking to weaken the fighting forces and will of its opponent through attrition. Each sought military victories to convince opposing leaders of the futility of continuing the contest. For the North Vietnamese, however, confrontation in the highlands had the additional purpose of relieving allied pressure in other areas, where pacification jeopardized their hold on the rural population. Of all the factors influencing operations in the highlands, the most significant may well have been the strength and success of pacification elsewhere. For Americans, the most difficult problem was to locate the enemy. Yet Communist strategists sometimes created threats to draw in the Americans. Recurrent menaces to Special Forces camps reflected the enemy's seasonal cycle of operations, his desire to harass and eliminate such camps, and his hope of luring allied forces into situations where he held the military advantages. Thus Army operations in the highlands during 1966 and 1967 were characterized by wide-ranging, often futile searches, punctuated by sporadic but intense battles fought usually at the enemy's initiative. For the first few months of 1966, the Communists lay low. In May, however, a significant concentration of enemy forces appeared in Pleiku and Kontum Provinces. The 1st Brigade, 101st Airborne Division, the reserve of I Field Force, was summoned to Pleiku and subsequently moved to Dak To, a CIDG camp in northern Kontum Province, to assist a besieged South Vietnamese force at the nearby government post at Tournorong. Although the 24th North Vietnamese Regiment had surrounded Tournorong, allied forces secured the road to Dak To and evacuated the government troops, leaving one battalion of the 101st inside the abandoned camp and one company in an exposed defensive position in the jungle a short distance beyond. On the night of 6 June a large North Vietnamese force launched repeated assaults on this lone company. Facing disaster, the commander called in air strikes on his own position to stop the enemy's human- wave attacks. Relief arrived the next morning, as additional elements of the brigade were heli-lifted to the battlefield to pursue and trap the North Vietnamese. Fighting to close off the enemy's escape routes, the Americans called in renewed air strikes, including B-52's. By 20 June enemy resistance had ended, and the NVA regiment that had begun the fighting, leaving behind dead, escaped to the safety of its Laotian base. Although the enemy's push in Kontum Province was blunted, the siege of Tournorong was only one aspect of his summer offensive in the highlands. Suspecting that NVA forces meant to return to the Ia Drang, Westmoreland sent the 3d Brigade, 25th Infantry Division, back into the valley in May. Dividing the area into "checkerboard" squares, the brigade methodically searched each square. Small patrols set out ambushes and operated for several days without resupply to avoid having helicopters reveal their location. After several days in one square, the patrols leapfrogged by helicopter to another. Though the Americans made only light, sporadic contacts, the cumulative toll of enemy killed was equal to many short, violent battles. One significant contact was made in late May near the Chu Pong Massif. A running battle ensued, as the enemy again sought safety in Cambodia. Westmoreland now appealed to Washington for permission to maneuver Army units behind the enemy, possibly into Cambodian territory. But officials refused, fearing international repercussions, and the NVA sanctuary remained inviolate. Yet the operation confirmed that sizable enemy forces had returned to South Vietnam and, as in the fall of 1965, were threatening the outposts at Plei Me and Duc Co. To meet the renewed threat, I Field Force sent additional Army units to Pleiku Province and launched a new operation under the 1st Cavalry Division. The action followed the now familiar pattern of extensive hell-lifts, establishment of patrol bases, and intermittent contact with an enemy who usually avoided American forces. When the Communists elected to fight, they preferred to occupy high ground; dislodging them from hilltop bunkers was a difficult task, requiring massive air and artillery support. By the time the enemy left Pleiku again at the end of August, his forces had incurred nearly 500 deaths. Border battles continued, however, and some were sharp. When enemy forces appeared in strength around a CIDG camp at Plei Djering in October, elements of the 4th Infantry and 1st Cavalry Divisions rapidly reinforced the camp, clashing with the enemy in firefights during October and November. As North Vietnamese forces began to withdraw through the Plei Trap valley, the 1st Brigade, 101st Airborne Division, was airlifted from Phu Yen to northern Konturn to try to block their escape, but failed to trap them before they reached the border. Army operations in the highlands were continued by the 4th Infantry Division. In addition to screening the border to detect infiltration, the division constructed a new road between Pleiku and the highland outpost at Plei Djering and helped the Saigon government resettle thousands of Montagnards in secure camps. Contact with the enemy generally was light, the heaviest occurring in mid- February 1967, in an area west of the Nam Sathay River near the Cambodian border, when Communist forces unsuccessfully tried to overrun several American fire bases. Despite infrequent contacts, however, 4th Division troops killed 7oo enemy over a period of three months. In I Corps as well, the enemy seemed intent on dispersing American forces to the border regions. Heightened activity along the demilitarized zone drew marines from southern I Corps. To replace them, Army units were transferred from III and II Corps to the area vacated by the marines, among them the 196th Infantry Brigade, which was pulled out of Operation JUNCTION CITY, and the 3d Brigade, 25th Infantry Division, which had been operating in the II Corps Zone. Together with the 1st Brigade, 101st Airborne Division, these units formed Task Force OREGON, activated on 12 April 1967 and placed under the operational control of the III Marine Amphibious Force. Army infantry units were now operating in all four of South Vietnam's corps areas. Once at Chu Lai, the Army forces supported an extensive South Vietnamese pacification effort in Quang Tin Province. To the north, along the demilitarized zone, Army heavy artillery engaged in almost daily duels with NVA guns to the north. In Quang Tri Province, the marines fought a hard twelve-day battle to prevent NVA forces from dominating the hills surrounding Khe Sanh. The enemy's heightened military activity along the demilitarized zone, which included frontal attacks across it, prompted American officials to begin construction of a barrier consisting of highly sophisticated electronic and acoustical sensors and strong point defenses manned by allied forces. Known as the McNamara Line, after Secretary of Defense Robert S. McNamara, who vigorously promoted the concept, the barrier was to extend across South Vietnam and eventually into Laos. Westmoreland was not enthusiastic about the project, for he hesitated to commit large numbers of troops to man the strongpoints and doubted that the barrier would prevent the enemy from breaching the demilitarized zone. Hence the McNamara Line was never completed. Throughout the summer of 1967, Marine forces endured some of the most intense enemy artillery barrages of the war and fought several battles with NVA units that infiltrated across the 17th parallel. Their stubborn defense, supported by massive counterbattery fire, naval gunfire, and air attacks, ended the enemy's offensive in northern I Corps, but not before Westmoreland had to divert additional Army units as reinforcements. A brigade of the 1st Cavalry Division and South Korean units were deployed to southern I Corps to replace additional marines who had been shifted further north. The depth of the Army's commitment in I Corps was shown by Task Force OREGON's reorganization as the 23d Infantry Division (Americal). The only Army division to be formed in South Vietnam, its name echoed a famous division of World War 11 that had also been organized in the Pacific. If the enemy's aim was to draw American forces to the north, he evidently was succeeding. Intensified Fighting Even as Westmoreland shifted allied forces from II Corps to I Corps, fighting intensified in the highlands. After Army units made several contacts with enemy forces during May and June, Westmoreland moved the 173d Airborne Brigade from III Corps to II Corps to serve as the I Field Force's strategic reserve. Within a few days, however, the brigade was committed to an effort to forestall enemy attacks against the CIDG camps of Dak To, Dak Seang, and Dak Pek in northern Kontum Province. Under the control of the 4th Infantry Division, the operation continued throughout the summer until the enemy threat abated. A few months later, however, reconnaissance patrols in the vicinity of Dak To detected a rapid and substantial build-up of enemy forces in regimental strength. Believing an attack to be imminent, 4th Infantry Division forces reinforced the garrison. In turn, the 173d Airborne Brigade returned to the highlands, arriving on 2 November. From 3 to 15 November enemy forces estimated to number 12,000 probed, harassed, and attacked American and South Vietnamese positions along the ridges and hills surrounding the camp. As the attacks grew stronger, more U.S. and South Vietnamese reinforcements were sent, including two battalions from the airmobile division and six ARVN battalions. By mid-November allied strength approached 8,000. Despite daily air and artillery bombardments of their positions, the North Vietnamese launched two attacks against Dak To on 15 November, destroying two C-13o aircraft and causing severe damage to the camp's ammunition dump. Allied forces strove to dislodge the enemy from the surrounding hills, but the North Vietnamese held fast in fortified positions. The center of enemy resistance was Hill 875; here, two battalions of the 173d Airborne Brigade made a slow and painful ascent against determined resistance and under grueling physical conditions,. fighting for every foot of ground. Enemy fire was so intense and accurate that at times the Americans were unable to bring in reinforcements by helicopter or to provide fire support. In fighting that resembled the hill battles of the final stage of the Korean War, the confusion at Dak To pitted soldier against soldier in classic infantry battle. In desperation, beleaguered U.S. commanders on Hill 875 called in artillery and even B-52 air strikes at perilously close range to their own positions. On 17 November American forces at last gained control of Hill 875 The battle of Dak To was the longest and most violent in the highlands since the battle of the la Drang two years before. Enemy casualties numbered in the thousands, with an estimated 1,400 killed. Americans had suffered too. Approximately one-fifth of the 173d Airborne Brigade had become casualties, with 174 killed, 642 wounded, and 17 missing in action. If the battle of the Ia Drang exemplified airmobility in all its versatility, the battle of Dak To, with the arduous ascent of Hill 875, epitomized infantry combat at its most basic and the crushing effect of supporting air power. Yet Dak To was only one of several border battles in the waning months of 1967. At Song Be and Loc Ninh in III Corps, and all along the northern border of I Corps, the enemy exposed his positions in order to confront U.S. forces in heavy fighting. By the end of 1967 the 1st Infantry Division had again concentrated near the Cambodian border, and the 25th Infantry Division had returned to War Zone C. The enemy's threat in I Corps caused Westmoreland to disperse more Army units. In the vacuum left by their departure, local Viet Cong sought to reconstitute their forces and to reassert their control over the rural population. In turn, Viet Cong revival often was a prelude to the resurgence of Communist military activity at the district and village level. Hard pressed to find additional Army units to shift from III Corps and 11 Corps to I Corps, Westmoreland asked the Army to accelerate deployment of two remaining brigades of the 101st Airborne Division from the United States. Arriving in December 1967, the brigades were added to the growing number of Army units operating in the northern provinces. While allied forces were under pressure, the border battles of 1967 also led to a reassessment of strategy in Hanoi. Undeviating in their long-term aim of unification, the leaders of North Vietnam recognized that their strategy of military confrontation had failed to stop the American military buildup in the South or to reduce U.S. military pressure on the North. The enemy's regular and main force units had failed to inflict a salient military defeat on American forces. Although the North Vietnamese Army maintained the tactical initiative, Westmoreland had kept its units at bay and in some areas, like Binh Dinh Province, diminished their influence on the contest for control of the rural population. Many Communist military leaders perceived the. war to be a stalemate and thought that continuing on their present course would bring diminishing returns, especially if their local forces were drastically weakened. On the other side, Westmoreland could rightly point to some modest progress in improving South Vietnam's security and to punishing defeats inflicted on several NVA regiments and divisions. Yet none of his successes were sufficient to turn the tide of the war. The Communists had matched the build-up of American combat forces, the number of enemy divisions in the South increasing from one in early 1965 to nine at the start of 1968. Against 320 allied combat battalions, the North Vietnamese and Viet Cong could marshal 240. Despite heavy air attacks against enemy lines of infiltration, the flow of men from the North had continued unabated, even increasing toward the end of 1967 Although the Military Assistance Command had succeeded in warding off defeat in 1965 and had gained valuable time for the South Vietnamese to concentrate their political and military resources on pacification, security in many areas of South Vietnam had improved little. Americans noted that the Viet Cong, in one district within artillery range of Saigon, rarely had any unit as large as a company. Yet, relying on booby traps, mines, and local guerrillas, they tied up over 6,000 American and South Vietnamese troops. More and more, success in the South seemed to depend not only on Westmoreland's ability to hold off and weaken enemy main force units, but on the equally important efforts of the South Vietnamese Army, the Regional and the Popular Forces, and a variety of paramilitary and police forces to pacify the countryside. Writing to President Johnson in the spring of 1967, outgoing Ambassador Henry Cabot Lodge warned that if the South Vietnamese "dribble along and do not take advantage of the success which MACV has achieved against the main force and the Army of North Vietnam, we must expect that the enemy will lick his wounds, pull himself together and make another attack in '68." Westmoreland's achievements, he added, would be "judged not so much on the brilliant performance of the U.S. troops as on the success in getting ARVN, RF and PF quickly to function as a first-class ... counter-guerrilla force." Meanwhile the war appeared to be in a state of equilibrium. Only an extraordinary effort by one side or the other could bring a decision. Back to Table of Contents -- US Army in Vietnam Back to Vietnam Military History List of Issues Back to MagWeb Magazine List © Copyright 2004 by Coalition Web, Inc. This article appears in MagWeb.com (Magazine Web) on the Internet World Wide Web. 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