Reposted from Marine Corps University: Marine Corps University > Research > Marine Corps History Division > Brief Histories > Marines in Vietnam: 1954-1975 (usmcu.edu)

The Advisory and Combat Assistance Era 1954-1964

For the United States Marine Corps, involvement in the nation’s longest war began on 2 August 1954 with the arrival of Lieutenant Colonel Victor J. Croizat as a liaison officer with the newly established United States Military Assistance and Advisory Group to the Republic of Vietnam. For the next eight years, Marine activities in Vietnam consisted mainly of advisory and staff responsibilities. This began to change in mid-April 1962 when Marine Medium Helicopter Squadron 362 (HMM-362), commanded by Lieutenant Colonel Archie Clapp, deployed to South Vietnam to provide combat service support for the fledgling South Vietnamese army. In the spring of 1964, Marine Detachment, Advisory Team One, commanded by Major Alfred M. Gray Jr., arrived to collect signals intelligence, thereby becoming the first Marine ground unit to arrive in the country.

Following the Gulf of Tonkin incident in August 1964, the Marine Corps commitment to Southeast Asia expanded further. The end of 1964 brought an end to the advisory and assistance phase of the Vietnam War. A crucial turning point had been reached and 1965 brought about a major escalation in Marine combat activities in Vietnam.

The Buildup 1965

On 22 February 1965, General William C. Westmoreland, USA, Commander, US Military Assistance Command, Vietnam, requested two Marine battalions to protect the key airbase at Da Nang from increasing threat by the Viet Cong to U.S. installations. In response, on 8 March 1965, the 9th Marine Expeditionary Brigade (MEB) landed at Da Nang. By the end of March, nearly 5,000 Marines were at Da Nang, including two infantry battalions, two helicopter squadrons and supply and logistics units. In April the U.S. Government agreed to deploy still more Marines to Vietnam and to permit those at Da Nang to engage in counterinsurgency operations. In June, Major General Lewis W. Walt arrived to take command of the newly formed III Marine Amphibious Force (MAF), comprising both the 3d Marine Division and the 1st Marine Aircraft Wing (MAW). By mid-summer, the Marines had moved outside their cantonment at Da Nang and expanded their Area of Responsibility (AOR) to include the Viet Cong infested villages to the south. Marines landed at Chu Lai, allowing the 1st Wing to expand to new facilities there and at Marble Mountain, home of Marine Aircraft Group (MAG) 36, while MAG-16 remained at the airbase at Da Nang.

In August, Marines engaged in their first major offensives against the Viet Cong, Operation Starlite, which included the 7th Marines, the vanguard of the 1st Marine Division. The action destroyed one Viet Cong battalion and badly mauled a second. By the end of the year, Gen Walt commanded 42,000 Marines. Despite operational successes, pacification in the densely populated areas in the Marine’s AOR remained a difficult process. With no end to the war in sight, the prediction of a Vietnamese soothsayer would come true: 1966 would be a year of a “lot of fighting and killing.”

An Expanding War 1966

In 1966, the size of U.S. Marine forces in the Republic of Vietnam continued to increase as the remaining units of the 1st Marine Division, commanded by Major General Lewis J. “Jeff” Fields, arrived from Okinawa to assist in pacifying the southern areas of I Corps. Even with its influx of Marines, a manpower shortage plagued III MAF, compounding an already difficult mission. Senior Marine commanders expressed strong disagreement with the conduct of the war by the leadership of the Military Assistance Command, Vietnam. The Marines pushed for a small-scale unit pacification program along the populated coastal areas, while the Army leadership in Saigon advocated large unit search and destroy operations against North Vietnamese units. These disagreements further hindered the ability of III MAF to conduct effective combat operations.

Despite these problems, the Marines continued to carry the fight to the enemy with several operations, most notably Operations Utah and Texas in southern I Corps and Operation Prairie in the north of I Corps. The Marines continued to refine a novel organizational concept, Combined Action Platoons, which merged a local Vietnamese militia platoon with a Marine infantry squad. The month of March saw the first arrival of CH-46 Sea Knight helicopters as a replacement for the aging Sikorsky UH-34, when HMM-46 landed at Marble Mountain, deploying from the USS Valley Forge. Meanwhile, Marine fixed-wing aircraft continued to strike targets as far north as Hanoi and Haiphong.

The year had brought a major buildup of U.S. Marine forces in Vietnam. Nearly 70,000 Marines were now in country; almost double the number from the pervious year. The hopes of the Marine commanders that increased troop strength would defeat the enemy proved unrealistic. The coming year would find the two divisions of III MAF fighting increasingly different wars. The 3d Marine Division was fighting a more conventional campaign against the North Vietnamese Army near the Demilitarized Zone (DMZ) in the north of I Corps while the 1st Marine Division engaged in more counter-guerrilla operations in Southern I Corps.

Fighting the Vietnamese 1967

While Marines continued conducting pacification and counter-guerrilla operations, most of the heavy fighting in 1967 raged in the north of I Corps along the DMZ. The 3d Marine Division engaged in heavy conventional fighting around the former Special Forces camp at Khe Sanh in the northwestern I Corps, to “Leatherneck Square” in the eastern DMZ. Simultaneously, Marines began construction of the “McNamara Line,” a series of strong points, sensors and obstacles designed to deter and detect Communist incursions across the DMZ. Never completed, the McNamara Line drained III MAF of scarce men and materiel. To counter it, the North Vietnamese conducted numerous attacks to destroy it in its infancy, all supported by heavy artillery fire. This resulted in several major engagements during the second half of 1967, most notably at Con Thien. All the while Marine air played a pivotal role in providing fire support, CH-46 and UH-34 helicopters remained the workhorses for logistics support, augmented that year by the first squadron of CH-53 Sea Stallions.

By year’s end, III MAF had blunted the North Vietnamese push across the DMZ. In all, U.S. Marines conducted 11 major operations of battalion size or larger and more than 356,000 smaller unit patrols and killed nearly 18,000 enemy. But the cost had been high, with 3,000 Marines killed including the 3d Marine Division commander, Major General Bruno A. Hochmuth. Despite augmentation by the Army’s Americal Division, III MAF remained stretched in both men and material. But the Marines believed they had made significant strides toward pacification during 1967. However, as 1968 approached, there were ominous indications of an even larger enemy invasion.

The Defining Year 1968 The year 1968 proved to be the decisive year for the Marines in Vietnam. Instead of the traditional cease-fire for the Tet Lunar New Year, the Communists launched a massive offensive against 105 cites and towns throughout South Vietnam. In the north, enemy forces attacked all the major population centers, including Da Nang and the old Imperial city of Hue. U.S. Marines and South Vietnamese forces repulsed all the attacks except at Hue. It would take 26 days of dogged house-to-house fighting to expel the North Vietnamese regulars from the city, as Marines, more accustomed to fighting in the steamy jungle, learned the difficult and bloody lessons of urban warfare.

While Tet raged, another drama was being played out at Khe Sanh. For 77 days the 26th Marines, commanded by Colonel David E. Lownds, held the embattled base against intense pressure by the North Vietnamese, who hurled as many as 1,000 shells a day into the Marine position. President Lyndon B. Johnson became so concerned over the siege that he had an exact model of the Khe Sanh base built to monitor the situation on the ground. But Marine tenacity and American air power inflicted grievous losses upon the enemy. On 6 April, the Army’s 1st Cavalry Division broke the siege.

1968 marked a turning point for the war in Vietnam. While the enemy had been defeated on the battlefield, American public opinion turned against the war. Television images of the fighting in Hue and Khe Sanh, and even at the U.S. Embassy in Saigon, eroded public support for the war. After three years of fighting, the enemy still appeared far from beaten. For many Americans, thoughts turned from escalation to winding down war in Vietnam.

High Mobility and Stand Down 1969

From the outset, the new President, Richard M. Nixon, committed his administration to reducing the level of U.S. forces in Vietnam. For the Marine Corps this meant a gradual reduction of forces in Vietnam. Incrementally, the Marine Corps began redeploying units, and by the end of the year, the entire 3d Marine Division had returned to Okinawa.

As planning to reduce force level in Vietnam continued, Marines continued to engage the enemy throughout I Corps. Colonel Robert H. Barrow’s 9th Marines began Operation Dewey Canyon, perhaps the most successful high-mobility regimental-sized action of the war. Over a two-month period, the Marines operated in the A Shau/Da Krong valleys. By 18 March, the enemy base area had been cleared out, killing more than 1,600 enemy. The Marine air-ground team proved its worth in greatly reducing enemy 122 mm rocket fire into Da Nang. Marine infantry, transported by helicopters, cleared out enemy positions in the rugged “Happy Valley” and “Charlie Ridges” areas, all supported by effective Marine fixed-wing aircraft.

Vietnamization and Redeployment 1970-1972

Throughout 1970, U.S. Marine forces continued to withdraw from Vietnam. The new policy emanating from Washington was “Vietnamization.” With U.S. airpower and advisors, the ground war was increasingly turned over to the South Vietnamese. While the invasion of Cambodia was the major military undertaking of 1970, only a limited number of Marine aviation assets were involved. Marines still conducted aggressive campaigns against the enemy, most notably Colonel Edmund G. Derning’s 7th Marines participation in Operation Pickens Forest and Colonel Paul X. Kelley’s 1st Marines actions near Da Nang. But by the end of 1970, more Marines were leaving than arriving as replacements. On 14 April 1971, III MAF redeployed to Okinawa, and two months later the last ground troops, the 13,000 men of the 3d MAB, flew out from Da Nang.

Although Marine combat units were no longer in Vietnam, Marine advisors remained to assist the South Vietnamese. During the North Vietnamese 1972 Easter Offensive, Marine advisors played a pivotal role in repelling the Communist attacks. Captain John W. Ripley, Captain Ray L. Smith and Captain Lawrence H. Livingston each won the Navy Cross for their heroic contributions in stopping the enemy advances.

The Bitter End 1973-1975

Following the failure of the Communists’ Easter Offensive and an intensive bombing campaign of North Vietnam, a peace treaty was finally signed in Paris on 27 January 1973. The U.S. agreed to withdraw all its forces from South Vietnam. The North, in turn, returned all the U.S. Prisoners of War, including 26 Marines. Unfortunately, peace was short lived in Vietnam, and in 1974 fighting resumed in both Cambodia and South Vietnam. By the spring of 1975, the situation became desperate for the U.S. backed governments in both Phnom Penh and Saigon. On 12 April, the 31st MAU, commanded by Colonel John F. Roche, executed a non-combatant evacuation, Operation Eagle Pull, the abandonment of the U.S. embassy in Phnom Penh prior to the city’s capitulation to Communist Khmer Rouge forces. Three weeks later, Marines were called upon to evacuate another embassy, this time in Saigon. Marines of the 9th MAB successfully executed Operation Frequent Wind, which safely removed hundreds of Americans and Vietnamese civilians prior to the fall of South Vietnam.

No sooner had the Marines evacuated the embassies than they were ordered by President Gerald R. Ford to rescue the crew of the USS Mayaguez, which had been taken by the Khmer Rouge. On 15 May, a Marine Task Force under the command of Colonel John M. Johnson recovered the Mayaguez and her crew, but not without high losses.

America’s longest war was costly to the U.S. Marine Corps. From 1965 to 1975, nearly 500,000 Marines served in Southeast Asia. Of these, nearly 13,000 were killed and 52,000 wounded; nearly a third of all American causalities sustained during the war.

Source: Reference Branch, Marine Corps History Division. Marine Corps University: Marine Corps University > Research > Marine Corps History Division > Brief Histories > Marines in Vietnam: 1954-1975 (usmcu.edu)