Battle of Khe Sanh

The village of Khe Sanh was the seat of government of Hương Hoa district, an area of Bru Montagnard villages and coffee plantations about from the Laotian frontier on Route 9, the northernmost transverse road in South Vietnam. The badly-deteriorated Route 9 ran from the coastal region through the western highlands and crossed the border into Laos. The origin of the combat base lay in the construction by US Army Special Forces of an airfield in August 1962 outside the village at an old French fort. James Marino wrote that in 1964, General William Westmoreland, the US commander in Vietnam, had determined, "Khe Sanh could serve as a patrol base blocking enemy infiltration from Laos; a base for... operations to harass the enemy in Laos; an airstrip for reconnaissance to survey the Ho Chi Minh Trail; a western anchor for the defenses south of the DMZ; and an eventual jumping-off point for ground operations to cut the Ho Chi Minh Trail." In November 1964, the Special Forces moved their camp to the Xom Cham Plateau, the future site of Khe Sanh Combat Base. In the winter of 1964, Khe Sanh became the location of a launch site for the highly classified Military Assistance Command, Vietnam – Studies and Observations Group. The site was first established near the village and later moved to the French fort. From there, reconnaissance teams were launched into Laos to explore and gather intelligence on the PAVN logistical system known as the Ho Chi Minh Trail, also known as "Truong Son Strategic Supply Route" to the North Vietnamese soldiers. The Marines' defensive system stretched below the Demilitarized Zone (DMZ) from the coast, along Route 9, to Khe Sanh. In 1966, the regular Special Forces troops had moved off the plateau and built a smaller camp down Route 9 at Lang Vei, about half the distance to the Laotian border. == Background ==

Border battles During the second half of 1967, the North Vietnamese instigated a series of actions in the border regions of South Vietnam. All of the attacks were conducted by regimental-size PAVN/VC units, but unlike most of the previous usual hit-and-run tactics, they were sustained and bloody affairs. In early October, the PAVN had intensified battalion-sized ground probes and sustained artillery fire against Con Thien, a hilltop stronghold in the center of the Marines' defensive line south of the DMZ, in northern Quảng Trị Province. Mortar rounds, artillery shells, and 122 mm rockets fell randomly but incessantly upon the base. The September bombardments ranged from 100 to 150 rounds per day, with a maximum on 25 September of 1,190 rounds. Westmoreland responded by launching Operation Neutralize, an aerial and naval bombardment campaign designed to break the siege. For seven weeks, American aircraft dropped between 35,000 and 40,000 tons of bombs in nearly 4,000 airstrikes. On 27 October, a PAVN regiment attacked an Army of the Republic of Vietnam (ARVN) battalion at Song Be, capital of Phước Long Province. US intelligence estimated between 1,200 and 1,600 PAVN troops were killed, and 362 members of the US 4th Infantry Division, the 173rd Airborne Brigade, and ARVN Airborne elements were killed in action, but three of the four battalions of the 4th Infantry and the entire 173rd were rendered combat-ineffective during the battle. American intelligence analysts were quite baffled by the series of enemy actions. No logic was apparent to them behind the sustained PAVN/VC offensives other than to inflict casualties on the allied forces. That was accomplished, but the casualties absorbed by the North Vietnamese seemed to negate any direct gains they might have obtained. The border battles, however, had two significant consequences, which were unappreciated at the time. They fixed the attention of the American command on the border regions, and they drew American and ARVN forces away from the coastal lowlands and cities in preparation for the Tet Offensive. Hill fights Things remained quiet in the Khe Sanh area through 1966. Even so, Westmoreland insisted for it not only to be occupied by the Marines but also for it to be reinforced. He was vociferously opposed by General Lewis W. Walt, the Marine commander of I Corps, who argued heatedly that the real target of the American effort should be the pacification and protection of the population, not chasing the PAVN/VC in the hinterlands. Westmoreland won out, however, and the 1st Battalion, 3rd Marine Regiment (1/3 Marines) was dispatched to occupy the camp and airstrip on 29 September. By late January 1967, the 1/3 returned to Japan and was relieved by Bravo Company, 1st Battalion, 9th Marines (1/9 Marines). A single company replaced an entire battalion. On 24 April 1967, a patrol from Bravo Company became engaged with a PAVN force of an unknown size north of Hill 861. That action prematurely triggered a PAVN offensive aimed at taking Khe Sanh. The PAVN forces were in the process of gaining elevated terrain before it launched the main attack. The 2nd and 3rd battalions of the 3rd Marine Regiment, under the command of Colonel John P. Lanigan, reinforced KSCB and were given the task of pushing the PAVN off of Hills 861, 881 North, and 881 South. PAVN forces were driven out of the area around Khe Sanh after suffering 940 casualties. The Marines suffered 155 killed in action and 425 wounded. To prevent PAVN observation of the main base at the airfield and their possible use as firebases, the hills of the surrounding Khe Sanh Valley had to be continuously occupied and defended by separate Marine elements. Lieutenant General Robert E. Cushman Jr. relieved Walt as commander of III MAF in June. On 14 August, Colonel David E. Lownds took over as commander of the 26th Marine Regiment. Sporadic actions were taken in the vicinity during the late summer and early fall, the most serious of which was the ambush of a supply convoy on Route 9. That proved to be the last overland attempt at resupply for Khe Sanh until the following March. Decisions A decision then had to be made by the American high command to commit more of the limited manpower in I Corps to the defense of Khe Sanh or to abandon the base. Westmoreland regarded the choice as quite simple. In his memoirs, he listed the reasons for a continued effort:Khe Sanh could serve as a patrol base for blocking enemy infiltration from Laos along Route 9; as a base for SOG operations to harass the enemy in Laos; as an airstrip for reconnaissance planes surveying the Ho Chi Minh Trail; as the western anchor for defenses south of the DMZ; and as an eventual jump-off point for ground operations to cut the Ho Chi Minh Trail. Not all leading Marine officers, however, had the same opinion. Cushman, the new III MAF commander, supported Westmoreland perhaps because he wanted to mend Army/Marine relations after the departure of Walt. Other concerns raised included the assertion that the real danger to I Corps was from a direct threat to Quảng Trị City and other urban areas, a defense would be pointless as a threat to infiltration since PAVN troops could easily bypass Khe Sanh, the base was too isolated, and the Marines "had neither the helicopter resources, the troops, nor the logistical bases for such operations." Additionally, Shore argued that the "weather was another critical factor because the poor visibility and low overcasts attendant to the monsoon season made such operations hazardous." Brigadier General Lowell English (assistant commander 3rd Marine Division) complained that the defense of the isolated outpost was ludicrous: "When you're at Khe Sanh, you're not really anywhere. You could lose it and you really haven't lost a damn thing." As far as Westmoreland was concerned, however, all that he needed to know was that the PAVN had massed large numbers of troops for a set-piece battle. Making the prospect even more enticing was that the base was in an unpopulated area in which American firepower could be fully employed without civilian casualties. The opportunity to engage and destroy a formerly elusive enemy that was moving toward a fixed position promised a victory of unprecedented proportions. == Battle ==

Attacks on the perimeter First skirmishes In early December 1967, the PAVN appointed Major General Trần Quý Hai as the local commander for the actions around Khe Sanh, with Lê Quang Đạo as his political commissar. In the coming days, a campaign headquarters was established around Sap Lit. Two divisions, the 304th and the 325th, were assigned to the operation: the 325th was given responsibility for the area around the north, while the 304th was given responsibility for the southern sector. At positions west of Hill 881 South and north of Co Roc Ridge (), across the border in Laos, the PAVN established artillery, rocket, and mortar positions from which to launch attacks by fire on the base and to support its ground operations. The PAVN 130 mm and 152 mm artillery pieces, and 122 mm rockets, had a longer range than the Marine artillery support which consisted of 105 mm and 155 mm howitzers. This range overmatch was used by the PAVN to avoid counter-battery fire. Nevertheless, ultimately the nuclear option was discounted by military planners. A secret memorandum reported by US Secretary of Defense Robert McNamara, sent to US President Lyndon B. Johnson on 19 February 1968, was declassified in 2005. It reveals that the nuclear option was discounted because of terrain considerations that were unique to South Vietnam, which would have reduced the effectiveness of tactical nuclear weapons. McNamara wrote: "because of terrain and other conditions peculiar to our operations in South Vietnam, it is inconceivable that the use of nuclear weapons would be recommended there against either Viet Cong or North Vietnamese forces". McNamara's thinking may have also been affected by his aide David Morrisroe, whose brother Michael Morrisroe was serving at the base. Operation Niagara During January, the recently installed electronic sensors of Operation Muscle Shoals (later renamed "Igloo White"), which were undergoing test and evaluation in southeastern Laos, were alerted by a flurry of PAVN activity along the Ho Chi Minh Trail opposite the northwestern corner of South Vietnam. Due to the nature of these activities, and the threat that they posed to KSCB, Westmoreland ordered Operation Niagara I, an intense intelligence collection effort on PAVN activities in the vicinity of the Khe Sanh Valley. Niagara I was completed during the third week of January, and the next phase, Niagara II, was launched on 21 January, the day of the first PAVN artillery barrage. Thus began what was described by John Morocco as "the most concentrated application of aerial firepower in the history of warfare". Westmoreland had already ordered the nascent Igloo White operation to assist in the Marine defense. By the end of the battle, USAF assets had flown 9,691 tactical sorties and dropped 14,223 tons of bombs on targets within the Khe Sanh area. Marine Corps aviators had flown 7,098 missions and released 17,015 tons. Naval aircrews, many of whom were redirected from Operation Rolling Thunder strikes against North Vietnam, flew 5,337 sorties and dropped 7,941 tons of ordnance in the area. Heated debate arose between Westmoreland, Commandant of the Marine Corps Leonard F. Chapman Jr., and Army Chief of Staff Harold K. Johnson. Johnson backed the Marine position due to his concern over protecting the Army's air assets from Air Force co-option. Fall of Lang Vei The Tet Offensive was launched prematurely in some areas on 30 January. On the following night, a massive wave of PAVN/VC attacks swept throughout South Vietnam, everywhere except Khe Sanh. The launching of the largest enemy offensive thus far in the conflict did not shift Westmoreland's focus away from Khe Sanh. A press release prepared on the following day (but never issued), at the height of Tet, showed that he was not about to be distracted. "The enemy is attempting to confuse the issue ... I suspect he is also trying to draw everyone's attention away from the greatest area of threat, the northern part of I Corps. Let me caution everyone not to be confused." Not much activity (with the exception of patrolling) had occurred thus far during the battle for the Special Forces Detachment A-101 and their four companies of Bru CIDGs stationed at Lang Vei. Then, on the morning of 6 February, the PAVN fired mortars into the Lang Vei compound, wounding eight Camp Strike Force soldiers. At 18:10 hours, the PAVN followed up their morning mortar attack with an artillery strike from 152 mm howitzers, firing 60 rounds into the camp. The strike wounded two more Strike Force soldiers and damaged two bunkers. Although the PAVN was known to possess two armored regiments, it had not yet fielded an armored unit in South Vietnam, and besides, the Americans considered it impossible for them to get one down to Khe Sanh without it being spotted by aerial reconnaissance. The USAF delivered 14,356 tons of supplies to Khe Sanh by air (8,120 tons by paradrop). 1st Marine Aircraft Wing records claim that the unit delivered 4,661 tons of cargo into KSCB. In addition, over 100,000 tons of bombs were dropped until mid-April by aircraft of the USAF, US Navy and Marines onto the area surrounding Khe Sanh. This equates to roughly 1,300 tons of bombs dropped daily – 5 tons for every one of the 20,000 PAVN soldiers initially estimated to have been committed to the fighting at Khe Sanh. Marine analysis of PAVN artillery fire estimated that the PAVN gunners had fired 10,908 artillery and mortar rounds and rockets into Marine positions during the battle. Attacks prior to relief of the base On the night of the fall of Lang Vei, three companies of the PAVN 101D Regiment moved into jump-off positions to attack Alpha-1, an outpost west of the Combat Base held by 66 men of Company A, 1st Platoon, 1/9 Marines. At 04:15 on 8 February under cover of fog and a mortar barrage, the PAVN penetrated the perimeter, overrunning most of the position and pushing the remaining 30 defenders into the southwestern portion of the defenses. For some unknown reason, the PAVN troops did not press their advantage and eliminate the pocket, instead throwing a steady stream of grenades at the Marines. Nevertheless, according to Tom Johnson, President Johnson was "determined that Khe Sanh [would not] be an 'American Dien Bien Phu'". He subsequently ordered the US military to hold Khe Sanh at all costs. As a result, "B-52 Arc Light strikes originating in Guam, Okinawa, and Thailand bombed the jungles surrounding Khe Sanh into stubble fields" and Khe Sanh became the major news headline coming out of Vietnam in late March 1968. Relief of Khe Sanh Operation Pegasus (1–14 April 1968) Planning for the overland relief of Khe Sanh had begun as early as 25 January 1968, when Westmoreland ordered General John J. Tolson, commander, First Cavalry Division, to prepare a contingency plan. Route 9, the only practical overland route from the east, was impassable due to its poor state of repair and the presence of PAVN troops. Tolson was not happy with the assignment, since he believed that the best course of action, after Tet, was to use his division in an attack into the A Shau Valley. Westmoreland planned on Khe Sanh being relieved and then used as the jump-off point for a "hot pursuit" of enemy forces into Laos. Regardless, on 1 April, Operation Pegasus began. Because of the close proximity of the enemy and their high concentration, the massive B-52 bombings, tactical airstrikes, and vast use of artillery, PAVN casualties were estimated by MACV as being between 10,000 and 15,000 men. Lownds and the 26th Marines departed Khe Sanh, leaving the defense of the base to the 1st Marine Regiment. He made his final appearance in the story of Khe Sanh on 23 May, when his regimental sergeant major and he stood before President Johnson and were presented with a Presidential Unit Citation on behalf of the 26th Marines. Operation Scotland II On 15 April, the 3rd Marine Division resumed responsibility for KSCB, Operation Pegasus ended, and Operation Scotland II began with the Marines seeking out the PAVN in the surrounding area. Author Peter Brush details that an "additional 413 Marines were killed during Scotland II through the end of June 1968". Regardless, the PAVN had gained control of a strategically important area, and its lines of communication extended further into South Vietnam. The gradual withdrawal of US forces began during 1969 and the adoption of Vietnamization meant that, by 1969, "although limited tactical offensives abounded, US military participation in the war would soon be relegated to a defensive stance." According to military historian Ronald Spector, to reasonably record the fighting at Khe Sanh as an American victory is impossible. Correspondent Michael Herr reported on the battle, and his account would inspire the surreal "Do Long Bridge" scene in the film Apocalypse Now, which emphasized the anarchy of the war. == Aftermath ==

Termination of the McNamara Line Commencing in 1966, the US had attempted to establish a barrier system across the DMZ to prevent infiltration by North Vietnamese troops. Known as the McNamara Line, it was initially codenamed "Project Nine". It was later renamed "Dye Marker" by MACV in September 1967, just as the PAVN began the first phase of their offensive by launching attacks against Marine-held positions across the DMZ. The attacks hindered the advancement of the McNamara Line, and as the fighting around Khe Sanh intensified, vital equipment including sensors and other hardware had to be diverted from elsewhere to meet the needs of the US garrison at Khe Sanh. Construction on the line was ultimately abandoned and resources were later diverted towards implementing a more mobile strategy. The question, known among American historians as the "riddle of Khe Sanh," has been summed up by John Prados and Ray Stubbe: "Either the Tet Offensive was a diversion intended to facilitate PAVN/VC preparations for a war-winning battle at Khe Sanh, or Khe Sanh was a diversion to mesmerize Westmoreland in the days before Tet." That has led other observers to conclude that the siege served a wider PAVN strategy by diverting 30,000 US troops away from the cities that were the main targets of the Tet Offensive. Whether the PAVN actually planned to capture Khe Sanh or the battle was an attempt to replicate the Việt Minh triumph against the French at the Battle of Dien Bien Phu has long been a point of contention. Westmoreland believed that the latter was the case, and his belief was the basis for his desire to stage "Dien Bien Phu in reverse." Other theories argued that the forces around Khe Sanh were simply a localized defensive measure in the DMZ area or that they were serving as a reserve in case of an offensive American end run in the mode of the American invasion at Inchon during the Korean War. However, North Vietnamese sources claim that the Americans did not win a victory at Khe Sanh but were forced to retreat to avoid destruction. The PAVN claimed that Khe Sanh was "a stinging defeat from both the military and political points of view." Westmoreland was replaced two months after the end of the battle, and his successor explained the retreat in different ways. He cited the fact that it would have taken longer to dislodge the North Vietnamese at Hue if the PAVN had committed the three divisions at Khe Sanh to the battle there instead of dividing its forces. However, the PAVN committed three regiments to the fighting from the Khe Sanh sector. Marine General Rathvon M. Tompkins, the commander of the 3rd Marine Division, pointed out that had the PAVN actually intended to take Khe Sanh, PAVN troops could have cut the base's sole source of water, a stream 500 m outside the perimeter of the base. If only it had contaminated the stream, the airlift would not have provided enough water to the Marines. Use during Operation Lam Son 719 On 30 January 1971, the ARVN and US forces launched Operation Dewey Canyon II, which involved the reopening of Route 9, securing the Khe Sanh area and reoccupying of KSCB as a forward supply base for Operation Lam Son 719. On 8 February 1971, the leading ARVN units marched along Route 9 into southern Laos while the US ground forces and advisers were prohibited from entering Laos. American logistical, aerial, and artillery support was provided to the operation. After the ARVN defeat in Laos, the newly reopened KSCB came under attack by PAVN sappers and artillery and the base was abandoned once again on 6 April 1971. == References ==