In the rugged, mist-shrouded highlands of South Vietnam's Quảng Trị Province, just a few miles from the Laotian border and the demilitarized zone (DMZ), lies a plateau known as Khe Sanh. In 1968, this remote outpost became the epicenter of one of the longest, deadliest, and most controversial battles of the Vietnam War. The 77-day siege of the Khe Sanh Combat Base pitted elite U.S. Marine and Army units against a numerically superior force of the People's Army of Vietnam (PAVN), creating a brutal crucible of attrition, airpower, and infantry resolve. The battle would become a symbol of the American war effort, highlighting both the immense destructive power of its military and the perplexing strategic questions that defined the conflict.

The Strategic Importance of a Remote Plateau

The establishment of a U.S. military presence at Khe Sanh began in 1962 when Army Special Forces constructed a small camp to work with local Montagnard tribesmen. By 1966, the U.S. Marines had taken over and expanded the site into a significant combat base. Its strategic value was rooted in its location. Positioned near the western terminus of the DMZ, Khe Sanh served as a critical anchor for the "McNamara Line," a proposed barrier of electronic sensors and strongpoints intended to interdict the flow of North Vietnamese soldiers and supplies into the South.

Right: 1967: Khe Sanh Marine base just south of the Demilitarized Zone (DMZ). U. S. Air Force C-130 on the makeshift air strip. Click to enlarge.

The base also served as a patrol hub for monitoring the Ho Chi Minh Trail, the vital logistical network that snaked through neighboring Laos and Cambodia. From Khe Sanh, American forces could launch reconnaissance missions and disrupt PAVN movements. However, this strategic location was also a vulnerability. Its isolation made it difficult to supply and reinforce by land, leaving it almost entirely dependent on air support. For General William C. Westmoreland, the commander of Military Assistance Command, Vietnam (MACV), holding Khe Sanh was non-negotiable. He saw it as an opportunity to draw large PAVN formations into a set-piece battle where America's superior firepower, particularly its airpower, could inflict devastating casualties. This "anvil and hammer" strategy aimed to destroy a significant portion of the North Vietnamese army.

For the North Vietnamese leadership in Hanoi, Khe Sanh presented a different kind of opportunity. By besieging the isolated Marine base, they aimed to achieve several objectives. A successful assault could create a major military and psychological victory, potentially replicating the success of the 1954 Battle of Dien Bien Phu, where Vietnamese forces overran a besieged French garrison, effectively ending French colonial rule in Indochina. The parallels were not lost on either side. President Lyndon B. Johnson, fearing a similar disaster, reportedly had a scale model of the Khe Sanh terrain built in the White House Situation Room and demanded assurances from his generals that the base would not fall.

Furthermore, the attack on Khe Sanh served as a massive diversion. By drawing significant U.S. forces and attention to the remote northwestern corner of South Vietnam, the PAVN hoped to pull American reserves away from the country's major urban centers, leaving them vulnerable to the widespread, coordinated attacks being planned for the Lunar New Year: the Tet Offensive.

The Gathering Storm: Prelude to the Siege

The prelude to the main siege began in late 1967. Intelligence reports and reconnaissance patrols indicated a massive buildup of PAVN forces in the region. The PAVN 325C Division was the first to be identified, followed by elements of the 304th and 320th Divisions. Notably, the 304th Division had been a key participant in the victory at Dien Bien Phu. This concentration of force, totaling an estimated 20,000 to 40,000 soldiers, signaled that a major confrontation was imminent.

Right: Ground Marines leave the temporary safety provided by Marine Air's CH-46. Click to Enlarge.

Photo Album: The Battle of Khe Sanh

In response, MACV reinforced the base. The primary defenders were the men of the 26th Marine Regiment, commanded by Colonel David E. Lownds. The regiment consisted of three battalions: the 1st, 2nd, and 3rd Battalions, 26th Marines (1/26, 2/26, 3/26). They were supported by the 1st Battalion, 13th Marines, which provided artillery support from within the base perimeter. The total American and South Vietnamese force at the main combat base and its surrounding hill outposts numbered around 6,000 men.

The terrain around Khe Sanh was dominated by a series of hills that provided critical observation and fields of fire over the base and its approaches. The Marines established combat outposts on several of these key features, designated by their height in meters: Hill 881 South, Hill 861, Hill 558, and Hill 950. These outposts, manned by rifle companies, would serve as the first line of defense, bearing the brunt of the initial PAVN assaults. The stage was set for a monumental clash. The first significant engagements, known as the "Hill Fights," occurred in April and May 1967, as Marines fought to secure this high ground. These bloody encounters were a grim foreshadowing of the larger battle to come.

The Siege Begins: 21 January 1968

The siege of Khe Sanh officially began in the early morning hours of 21 January 1968. At 00:30, Hill 861 was struck by a barrage of mortars and rocket fire, followed by a ground assault by a PAVN battalion. The Marines of Kilo Company, 3rd Battalion, 26th Marines, held their ground in brutal, close-quarters combat. A simultaneous attack was launched against the village of Khe Sanh, defended by South Vietnamese forces and a U.S. Marine Combined Action Platoon.

At 05:30, the main combat base itself came under a massive artillery bombardment. A shell struck the main ammunition supply point, which contained over 1,500 tons of explosives. The resulting explosion was cataclysmic, sending a fireball and mushroom cloud high into the air. The blast destroyed 98% of the available ammunition, killed 18 Americans, and wounded 43. It was a devastating opening blow, crippling the base's artillery capability and demonstrating the accuracy and power of the PAVN artillery hidden in the surrounding hills and across the border in Laos.

From that day forward, life for the defenders of Khe Sanh devolved into a grim routine of survival. The PAVN subjected the base to a relentless, daily barrage of artillery, rocket, and mortar fire, averaging over 150 rounds per day. Marines and soldiers lived in reinforced bunkers and trenches, a muddy, rat-infested subterranean world. Any movement above ground, whether to resupply a position, retrieve rations, or evacuate the wounded, was a life-threatening gamble known as the "Khe Sanh shuffle"—a mad dash from one covered position to the next.

Operation Niagara: The Airpower Unleashed

With the base cut off by land, resupply and fire support fell entirely to the U.S. Air Force, Navy, and Marine Corps aviation. The massive aerial campaign orchestrated to defend Khe Sanh was codenamed Operation Niagara, a name chosen by General Westmoreland to evoke a cascading waterfall of bombs. And cascade they did.

Right: U.S. Marines at Hill 881. Click to enlarge.

Operation Niagara was one of the most intense aerial bombardments in military history. On an average day, hundreds of tactical fighter-bombers, including F-4 Phantoms and A-4 Skyhawks, pounded PAVN positions around the base. Every 90 minutes, a cell of three B-52 Stratofortress bombers would arrive for an "Arc Light" strike. Flying at altitudes over 30,000 feet, they were unseen and unheard until their massive payloads of 500- and 750-pound bombs rained down. These strikes, guided by ground-based radar and sensors, carpeted huge swathes of the jungle, obliterating PAVN trenches, supply caches, and troop concentrations. The sheer destructive force of the B-52s was terrifying and highly effective, breaking up numerous planned assaults before they could even begin.

Supplying the base was a feat of incredible bravery and skill. C-130 Hercules, C-123 Providers, and C-7 Caribous became the lifeline for the besieged garrison. They flew through a gauntlet of anti-aircraft fire and mortars to land on the base's single metal runway. As the siege intensified and the runway became too dangerous, pilots resorted to high-speed, low-level approaches to drop supplies without landing (Low Altitude Parachute Extraction System, or LAPES) or simply kicked pallets out the back onto the runway in a "speed-offload." Helicopters, primarily the CH-46 Sea Knight and CH-53 Sea Stallion, braved heavy fire to deliver supplies to the outlying hilltops and, crucially, to evacuate the wounded. The aircrews who flew these missions suffered heavy losses but never faltered, ensuring the defenders never ran out of ammunition, food, or medical supplies.

The Fighting on the Ground: Outposts and Patrols

While airpower kept the PAVN at bay, the infantry war on the ground was intimate and savage. The heaviest fighting often occurred at the hilltop outposts and during patrols sent out from the main base.

On 5 February, PAVN forces launched a major assault to capture Hill 861A and Hill 881 South, two of the most critical outposts. The attacks were preceded by intense artillery fire and were carried out with fierce determination. The Marines defending these positions engaged in desperate hand-to-hand combat, using rifles, grenades, and bayonets to repel waves of attackers. Though the PAVN forces managed to briefly overrun sections of the outposts, determined counterattacks by the Marines ultimately pushed them back. The cost was high on both sides.

Another focal point of the ground war was the small outpost at Lang Vei, a Special Forces camp located about five miles west of the Khe Sanh Combat Base. Manned by U.S. Army Green Berets and Montagnard tribesmen, Lang Vei was attacked on the night of 7 February. This assault was significant because it marked the first time the PAVN used tanks—Soviet-made PT-76 amphibious light tanks—in South Vietnam. The defenders, equipped primarily with M72 LAW anti-tank rockets, found them largely ineffective against the armor. The camp was overrun in a brutal night of fighting. Survivors, many of them wounded, had to make a harrowing escape through enemy lines to reach the perimeter of the Khe Sanh base. The fall of Lang Vei tightened the noose around the main base and demonstrated the PAVN's growing sophistication and firepower.

Right: Trying to find cover during an NVA mortar or artillery attack. Click to enlarge.

For the Marines inside the main base, the ground war was one of patrols and perimeter defense. Despite the constant shelling, Colonel Lownds insisted on an "active defense," sending out patrols to gather intelligence, ambush enemy units, and keep the PAVN from digging their trenches too close to the wire. These patrols were exceptionally dangerous missions. One of the most infamous was the "Ghost Patrol" of 25 February. A platoon from Bravo Company, 1st Battalion, 26th Marines, was sent to locate a PAVN mortar position. They walked into a perfectly planned and executed ambush. Of the 48 men in the platoon, only a handful made it back to the base; the rest were killed, wounded, or captured. The incident underscored the deadly nature of the battlefield just beyond the perimeter wire.

The Defenders: Units in the Crucible

The defense of Khe Sanh was primarily a U.S. Marine Corps operation, but it involved a multi-service effort.

U.S. Marine Corps: The core of the defense was the 26th Marine Regiment. Colonel Lownds’ command included:

• 1st Battalion, 26th Marines (1/26): Fought some of the most intense battles, including the Ghost Patrol tragedy.

• 2nd Battalion, 26th Marines (2/26): Held key sectors of the main base perimeter and conducted dangerous patrols.

• 3rd Battalion, 26th Marines (3/26): Defended the critical hilltop outposts, including the initial assaults on Hill 861.

These infantry battalions were supported by the artillerymen of the 1st Battalion, 13th Marines, whose howitzers provided crucial fire support despite the catastrophic loss of their ammunition dump on the first day. The 1st Battalion, 9th Marines, a unit that had earned the grim nickname "The Walking Dead" for its high casualty rates in other operations, was flown in to reinforce the base in late January.

U.S. Army: The Army played a vital, though less numerous, role. The men of the 5th Special Forces Group at Lang Vei were among the first to face a direct ground assault. The most significant Army contribution was Operation Pegasus, the relief effort. The 1st Cavalry Division (Airmobile), with its vast fleet of helicopters, was tasked with breaking the siege by land. Their "air cavalry" tactics, leaping from hilltop to hilltop, were perfectly suited for the rugged terrain. They were joined by the 1st Marine Regiment and the 3rd ARVN Airborne Task Force.

Army of the Republic of Vietnam (ARVN): The 37th ARVN Ranger Battalion was positioned at the Khe Sanh base, defending a key sector of the eastern perimeter. Their steadfast performance under fire was commendable and often overlooked in accounts of the battle.

Operation Pegasus: The Relief of Khe Sanh

By the end of March, the strategic situation had changed. The Tet Offensive had been a military disaster for the Viet Cong and PAVN. Across South Vietnam, the surprise attacks on cities had been repulsed with enormous losses. With the main thrust of the offensive broken, MACV could finally turn its full attention to relieving Khe Sanh.

Right: 16 April 1968: U.S. Army's 1st Cavalry Division and staging area for Operation Pegasus. Click to enlarge.

On 1 April 1968, the U.S. Army's 1st Cavalry Division launched Operation Pegasus. The plan was a combined arms and joint service effort. The 1st Marine Regiment advanced westward along the vital Route 9, clearing the road of mines and ambushes, while the 1st Cavalry's helicopter-borne troops leapfrogged ahead, seizing key terrain and establishing firebases to support the advance. The PAVN, weakened by months of relentless bombing and having already achieved their strategic objective of a diversion, offered only scattered resistance.

On 6 April, troopers from the 2nd Battalion, 7th Cavalry, linked up with the Marines of the 26th Regiment at the combat base. By April 8, Route 9 was declared open. The 77-day siege was officially over. General Westmoreland flew into the base and declared a major victory for the United States, citing the staggering enemy losses.

Aftermath and Legacy: Withdrawal, Operations, and the True Outcome at Khe Sanh

The Battle of Khe Sanh, officially fought from 21 January to 9 July 1968, stands as one of the Vietnam War’s most significant and protracted engagements. The relief of the base in April 1968 did not mark the immediate cessation of combat activities in the region. Following the lifting of the siege, U.S. forces initiated Operation Scotland II—a continuation of previous operations in the Khe Sanh area, with objectives centered on reestablishing security, conducting search and destroy missions, and countering renewed PAVN activity. Operation Scotland II formally began on 15 April 1968, succeeding Operation Pegasus.

Throughout Operation Scotland II, the 1st Marine Division, elements of the 9th Marine Regiment, and supporting Army units conducted aggressive sweeps around the combat base and into the surrounding high ground. The operation sought to prevent further PAVN infiltration along the border and disrupt enemy concentrations. Despite the tactical intensity of these engagements, the strategic situation had shifted, with U.S. and South Vietnamese command reassessing the base's necessity in the evolving conduct of the war.

In the following months, mounting evidence indicated that the North Vietnamese, having suffered heavy losses during the siege and the Tet Offensive, were regrouping. Sporadic clashes continued, and Khe Sanh frequently endured artillery harassment and small-scale attacks. By the early summer of 1968, General Creighton Abrams—now Commanding General, MACV—advocated for a new approach. The strategic focus shifted from holding fixed positions, such as Khe Sanh, to emphasizing mobile operations and greater use of air mobility. The isolated nature of the base and the difficulty of maintaining lines of supply factored heavily into the decision.

This reevaluation culminated in Operation Charlie, which directed the planned withdrawal and evacuation of all allied personnel and materiel from Khe Sanh. Executed between late June and early July 1968, the operation involved coordinated actions by Marine, Army, and ARVN units. The withdrawal was conducted methodically to deny the enemy any opportunity to inflict casualties or capture large quantities of equipment.

During Operation Charlie, U.S. forces systematically destroyed bunkers, airstrips, ammunition, and defensive works, ensuring that nothing of military value remained for the enemy. The evacuation was completed under the constant threat of enemy observation and artillery fire. On 5 July 1968, the final elements of the 26th Marine Regiment departed the base. The official closure of Khe Sanh Combat Base was marked on 9 July 1968, formally ending nearly six months of continuous fighting in the area.

Right: 21 June 1968: U.S. Marine infantry bringing their wounded and dead to a CH-46. Click to enlarge.

The question of who ultimately prevailed at Khe Sanh remains the subject of considerable analysis. On a tactical level, the United States and its allies maintained control of the base throughout the siege, repelled repeated PAVN assaults, and inflicted disproportionate casualties on the attacking force. Estimates place PAVN losses at between 10,000 and 15,000 killed, though the true number remains uncertain. American losses were officially listed as 205 killed in action and over 1,600 wounded, not including some associated casualties among supporting aircrews and in the broader operational area.

Senior U.S. commanders, including General Westmoreland, cited the defense of Khe Sanh as evidence of American resolve and military superiority. President Johnson and military leaders presented the siege’s outcome as a significant victory. However, the strategic calculus extended beyond the battlefield. The primary North Vietnamese goal was not necessarily to capture Khe Sanh, but to draw allied forces away from South Vietnam’s urban centers and create a diversion ahead of the Tet Offensive. In this, they achieved a key objective. The American response to Khe Sanh concentrated tremendous resources in a remote area just as major coordinated attacks erupted elsewhere during Tet, undermining confidence in U.S. progress and policy.

The decision to evacuate and destroy Khe Sanh in July 1968, mere months after withstanding the siege at great cost, remains a controversial aspect of the campaign. Many American personnel who defended the position expressed confusion and frustration that hard-won ground, declared vital to strategy, was ultimately relinquished. The complex legacy of Khe Sanh is thus intertwined with the shifting priorities and ambiguities that characterized American involvement in Vietnam.

In terms of losses, the U.S. suffered 274 killed and 2,541 wounded at Khe Sanh. While the battle may have distracted American and South Vietnamese attention from the buildup of Viet Cong forces in the south before the early 1968 Tet Offensive, the US commander during the battle, General William Westmoreland, maintained that the true intention of Tet was to distract forces from Khe Sanh. Historian Max Hastings writes that

Westmoreland endowed Khe Sanh with an importance that it did not deserve; like Dienbienphu, the place should probably never have been garrisoned. Worse, he allowed the world to see where his gaze was fixed, which made him appear foolish--indeed, helped to destroy his reputation--when the enemy struck elsewhere. Nonetheless, it seems mistaken to imagine that the North Vietnamese deployed two divisions solely as a deception.... Communist officers later lamented the fact that the two formations had not instead been committed farther east, preferably at Hue. (Hastings 2018, 442)

The Battle of Khe Sanh, framed by the relentless struggle for the combat base, Operation Scotland II’s ongoing security operations, and Operation Charlie’s orderly withdrawal, encapsulates both the tactical prowess and the operational paradoxes of the Vietnam War. The engagement stands as a testament to the courage and discipline of the individual Marine, soldier, and airman, but also as a case study in the broader strategic dilemmas and enduring costs of protracted conflict in Southeast Asia.

Bibliography:

Archer, Michael. "A Deadly Dilemma: At the height of the Vietnam War, the Khe Sanh battlefield turned the Marine Corps’ most cherished virtue of Semper Fidelis into a liability." Cloudflare. Accessed November 7, 2023. https://www.usni.org/magazines/naval-history-magazine/2023/august/deadly-dilemma.

Bowden, Mark. Hue 1968: A Turning Point of the American War in Vietnam. New York: Atlantic Monthly Press, 2017.

Hammel, Eric. Khe Sanh: Siege in the Clouds. Havertown: Casemate, 2018.

Hastings, Max. Vietnam: An Epic Tragedy, 1945-1975. New York: Harper Perennial, 2018.

Karnow, Stanley. Vietnam: A History. New York: Viking, 1983.

Wawro, Geoffrey. The Vietnam War: A Military History. New York: Basic Books, 2024.