1971 - Laotian Incursion / LAM SON 719

Despite equivocal results in Cambodia, less than a year later the Americans pressed the South Vietnamese to launch a second cross-border operation, this time into Laos. Although the United States would provide air, artillery, and logistical support, Army advisers would not accompany South Vietnamese forces. The Americans' enthusiasm for the operation exceeded that of their allies. Anticipating high casualties, South Vietnam's leaders were reluctant to involve their army once more in extended operations outside their country.

The Ho Chi Minh Trail was an ever-changing network of paths and roads. For North Vietnam, keeping the Ho Chi Minh Trail open was a top priority. American intelligence had detected a North Vietnamese buildup in the vicinity of Tchepone, Laos, a logistical center on the Ho Chi Minh Trail approximately twenty-five miles west of the South Vietnamese border. The Military Assistance Command regarded the buildup as a prelude to a North Vietnamese spring offensive in the northern provinces. Like the Cambodian incursion, the Laotian invasion was justified as benefiting Vietnamization, but with the added bonuses of spoiling a prospective offensive and cutting off the Ho Chi Minh Trail. This would be the last chance for the South Vietnamese to cut the Ho Chi Minh Trail while American forces were available to provide support.

A decade earlier military analysts had developed plans to use corps-size American and allied forces to block the infiltration routes in Laos permanently as part of the overall defense of Southeast Asia. While the political climate in Washington had militated against widening the ground war, officials had viewed the sanctuaries in Laos as a strategic threat to the South sufficient to justify taking some form of punitive action against them. A bombing campaign, accordingly, started early, at the end of 1964, initially complementing the air raids against the North and the air war in South Vietnam but intensifying after the bombing halt over the North in 1968. Bases outside South Vietnam had been strictly off limits to allied ground forces. This rankled U.S. commanders, who regarded the restriction as a potentially fatal mistake. By harboring enemy forces, command facilities, and logistical depots, Cambodian and Laotian bases threatened all the progress the allies had made in the South since Tet 1968. To the Nixon administration, Abrams' desire to attack the Communist sanctuaries had the special appeal of gaining more time for Vietnamization.

In late 1970 Commander in Chief, Pacific (CINCPAC), Admiral John S. McCain, Jr. anticipated a massive logistics effort by the enemy during the coming dry season. President Nixon sensed an opportunity to strike a decisive blow against Hanoi. Senior policymakers in Washington and Saigon were buoyed up by the apparent success of the Cambodian operation. When Ambassador Ellsworth T. Bunker met the Joint Chiefs of Staff (JCS) on 18 November 1970, he told them that everyone should be pleased with the military aspects of the war and the progress of Vietnamization.

Planning for the invasion of Laos in a belated attempt to restrict the flow of supplies down the Ho Chi Minh Trail began in extreme secrecy. In December 1970 the Joint Chiefs of Staff authorized MACV to prepare for an invasion of the enemy base areas opposite I Corps; but, fearing leaks from the South Vietnamese, General Abrams told only his immediate staff, South Vietnamese president Thieu, and the top South Vietnamese general, Cao Van Vien. So tightly held was information on the impending operation that logistical and signal preparations that required long lead time were put in jeopardy and a combined tactical command post was not established until well into the offensive.

A four-pronged effort was planned: an ARVN attack up Route 9 to Tchepone; an operation by the ARVN 9th Division to clear Route 7 in Cambodia; an excursion into the Chup plantation; and covert operations against North Vietnam. President Nixon stated that the objective of these operations was "an enduring South Vietnam." McCain called it "an exceptional opportunity to inflict the maximum damage against enemy personnel, materiel, and psychological pressure." The White House, however, was intensely concerned about the parlous state of congressional and public support for the war. President Nixon wanted the thrust presented to the media not as an invasion but as a raid into the Laotian sanctuaries, so that there could be no perception of defeat.

Phase I, designated DEWEY CANYON II, began at 0001 local time on 30 January, as US troops maneuvered to secure western Quang Tri province. An assault airstrip became operational at Khe Sanh by 3 February; Route 9 was repaired and cleared to the Laotian border by 5 February. Behind this cover, the better part of two South Vietnamese divisions massed at Khe Sanh in preparation for the crossborder attack.

On 4 February, President Nixon authorized Phase II. Secretary Laird approved an execute message that would terminate operating authorities on 5 April, thereby limiting the Tchepone operation to six to eight weeks. Admiral Moorer promptly told Brigadier General Haig that he had "implored" Secretaries Laird and William P. Rogers not to impose a termination date and tell Congress about it, as the administration had done during the Cambodian incursion. The White House at once agreed that 5 April would not be treated as a deadline. Phase II opened on 8 February. The Vietnamese name, LAM SON 719, was given to operations in Laos.

Because of security leaks, the North Vietnamese were not deceived. Within a week South Vietnamese forces numbering about 17,000 became bogged down by heavy enemy resistance, bad weather, and poor attack management. The ARVN had run into a superior North Vietnamese force fighting on a battlefield that the enemy had carefully prepared. In midsummer 1970, the People's Army of Vietnam (PAVN) General Staff began drawing up combat plans, deploying forces, and directing preparation of the battlefield. By 8 February 1971, when the ARVN crossed the Laotian border, the North Vietnamese, by their own account, had massed some 60,000 troops in the Route 9-Southern Laos front. They included five main force divisions, two separate regiments, eight artillery regiments, three engineer regiments, three tank battalions, six anti-aircraft regiments, and eight sapper battalions, plus logistic and transportation units-according to North Vietnamese historians "our army's greatest concentration of combined-arms forces . . . up to that point."

The North Vietnamese had massed this combat power for a larger purpose than simply defending their critical supply route. They saw and were determined to seize an opportunity to fight a decisive battle on advantageous terms, destroy a large portion of Saigon's army, and thoroughly disrupt and discredit Vietnamization. What the allies had envisioned as a search-and-destroy operation similar to those in Cambodia turned into an intense combined arms conventional battle for which the ARVN was poorly prepared.

At a JCS meeting on 24 February 1971, General Westmoreland told the Service chiefs that he considered LAM SON 719 to be "a very high risk operation." His conclusions were that the operation had not gone according to plan, surprise was lost, resistance had proved greater than expected, the ARVN was attacking on a narrow rather than a broad front, and that Tchepone itself was open and flat, so that the surrounding high ground must be occupied.

Thieu's new plan called for two Marine brigades to replace the airborne and ranger units; two regiments of the 1st Division would advance northwest. "At the conclusion of these operations," ARVN units would withdraw along Routes 9 and 922 back into South Vietnam. On 1 March, General Abrams cabled Washington an assurance: ". . . [I]t is clear to me that President Thieu and General Vien are determined to fight these two hard battles [at Tchepone and Chup]. They realize their casualties will be high but they will take it and fight the battle to win."

Aided by heavy U.S. air strikes, including B-52s, and plenty of artillery and helicopter gunship support, the South Vietnamese inched forward and after a bloody, month-long delay, air-assaulted on March 6 into the heavily bombed town of Tchepone. This was the last bit of good news from the front.

This was the RVNAF's last chance to make a dramatic impression upon the North Vietnamese. The North Vietnamese by now had massed five divisions with perhaps 45,000 troops-more than twice the ARVN force in Laos-for counterattacks. The North Vietnamese counterattacked with Soviet- built tanks, heavy artillery, and infantry. They struck the rear of the South Vietnamese forces strung out on Highway 9, blocking their main avenue of withdrawal. Enemy forces also overwhelmed several South Vietnamese firebases, depriving South Vietnamese units of desperately needed flank protection. The South Vietnamese also lacked enough antitank weapons to counter the North Vietnamese armor that appeared on the Laotian jungle trails and were inexperienced in the use of those they had. U.S. Army helicopter pilots flying gunship and resupply missions and trying to rescue South Vietnamese soldiers from their besieged hilltop firebases encountered intense antiaircraft fire.

On March 16, ten days after Tchepone was taken, President Thieu issued the order to pull out, turning aside General Abrams' plea for an expansion of the offensive to do serious damage to the trail. The redeployment of ARVN forces fueled the pessimistic press reports claiming a rout of Vietnamese units from Laos, undermining widespread confidence in the success of Vietnamization. The South Vietnamese had suffered many more casualties than they had reported. A Vietnamese presidential election was slated for September, and a lengthy casualty list would alienate voters. The ARVN withdrawal, conducted mainly along Route 9, ran from 17 until 24 March. A North Vietnamese ambush on 19 March littered the road with wrecked vehicles. Artillery pieces were abandoned, and a good many men had to make their way on foot to landing zones for evacuation. American media carried pictures of ARVN soldiers clinging to the skids of US helicopters.

The South Vietnamese lost nearly 1,600 men. The U.S. Army's lost 215 men killed, 1,149 wounded, and 38 missing. The Army also lost 108 helicopters, the highest number in any one operation of the war. Supporters of helicopter warfare pointed to heavy enemy casualties and argued that equipment losses were reasonable, given the large number of helicopters and helicopter sorties (more than 160,000) that supported LAM SON 719. The battle nevertheless raised disturbing questions among Army officials about the vulnerability of helicopters in mid- or high-intensity conflict to any significant antiaircraft capability.

In retrospect, the "moment of truth" had revealed the Saigon government's shortcomings. President Thieu's performance during LAM SON 719 resembled President Ngo Dinh Diem's policy of preserving politically dependable units and declaring phantom victories, although in Thieu's case caution perhaps was justifed considering the unexpected strength of the opposition in Laos. Perhaps LAM SON 719 gave South Vietnam a year's respite. Probably, though, this display of the RVNAF's weakness emboldened Hanoi to bid for victory in 1972. Hanoi's official history declared in retrospect that the "Route 9-Southern Laos victory" marked "a new level of maturity for our army and was a concrete demonstration . . . that our army and people were strong enough to militarily defeat the 'Vietnamization' strategy of the American imperialists."

New York Times reporter Gloria Emerson interviewed ARVN survivors at Khe Sanh and concluded that their morale was shattered. "What has dramatically demoralized many of the South Vietnamese troops is the large number of their own wounded who were left behind, begging for their friends to shoot them or to leave hand grenades so they could commit suicide before the North Vietnamese or the B-52s killed them." According to Life magazine "the NVA drove the invading forces out of Laos with their tails between their legs."