Operation Phou Phiang II

The Kingdom of Laos contained a Communist insurrection from its moment of independence. U.S. financial and military support of Laos began in 1953, and intensified through the succeeding years as the Laotian Civil War heated up.[1] In 1961, the Central Intelligence Agency began arming and training hill tribes guerrillas on and around the strategic Plain of Jars.[2] The Hmong soldiers of L'Armée Clandestine would fight the invading People's Army of Vietnam until the ceasefire of February 1973.[3]

In the aftermath of the January 1972 Campaign Z, and its two counters, Operation Strength I and Operation Strength II, the strategic Lao guerrilla base at Long Tieng was at serious risk of capture by the People's Army of Vietnam (PAVN) until the rainy season gummed up military operations. Royalist radio intercepts began reporting the withdrawal of the PAVN 312th Division as early as 26 April 1972. On 17 May 1972, the rains came. The 312th Division had been withdrawn from the Plain of Jars (PDJ) to fight in the Easter Offensive striking South Vietnam; this considerably weakened the Communist forces in northern Laos. The Vietnamese Communist supply lines began to literally bog down and wash out in the monsoon downpour.[4]

PAVN strength was reduced to four regiments; however, they had supporting arms. The 174th Regiment garrisoned Phou Phasai, Zebra Ridge, and a regimental headquarters. The 866th Independent Regiment occupied the Plain; it was supported by pairs of T-34 and PT-76 tanks, and of 85mm and 122mm field guns. The 148th and 335th Independent Regiments were reserve units. The 42nd Artillery Battalion had its ten artillery pieces manning three fire bases. Also available were two sapper units, the 27th and 421st Dac Cong Battalions; three anti-aircraft battalions; an armored unit equipped with six T-59 and two T-34 tanks, as well as four K-63 armored personnel carriers.[5]

Opposed to them were a bewildering hodgepodge of Royalist Hmong guerrillas and Thai mercenaries in shifting assignments and alignments. During April and May 1972, three regimental-size guerrilla Groupements Mobile (GMs) were circulated south into Thailand for refurbishing—GMs 24, 23, and 22. Task Force Vang Pao, a formation of Thai mercenaries, contained at least six battalions. Five guerrilla battalions were stationed at Ban Pa Dong—Bataillons Guerrier (BGs) 105, 110, 209, 228, and 233. Another guerrilla battalion, BG 224, was stationed on Skyline Ridge, overlooking Long Tieng. Two reinforcement regiments would arrive from neighboring Military Region 3—GM 30 would be flown in on 18 May; GM 31 arrived on 2 July.[6]

Air superiority for the guerrillas would be guaranteed. They were allotted up to 80 Royal Lao Air Force (RLAF) T-28 Trojan sorties daily for close air support. The U.S. Air Force pledged 20 daily close air support sorties by F-4 Phantom IIs and six by A-1 Skyraiders. Ten more Phantom sorties were promised for interdiction missions. The operation's daily air support also included a B-52 Arc Light strike (with two more on call), as well as one AC-130 and four AC-119 gunship sorties.[7][8]

With PAVN strength reduced to four regiments, the Royalist forces felt free to both refit their worn units and push the Vietnamese for territory. On 8 May, two Royalist columns moved out; one was aimed at Sam Thong, the other at Phou Phasai. On 11 May 1972, six Bataillons Commando (BCs) of Thai mercenaries recaptured the refugee relief center at Sam Thong; they established two artillery fire bases in the vicinity.[6]

The Phou Phasai probe was a different matter. On 22 May, two Thai BCs that had been withdrawn in the midst of Operation Sinsay joined the fresh reinforcements of GM 30 to attack the mountaintop position the PAVN valued as a base for assaults on the Royalists. On the 25th, they were halted by the fresh PAVN troops that had manned the hilltop, and stalemated.[6]

In late May, Laotian General Vang Pao flew to Washington, DC to lobby for support for an offensive. He updated William H. Sullivan, with whom he had worked for four years. Sullivan was noncommittal. Melvin Laird had some issues with the use of B-52 Stratofortresses as tactical air power. On the other hand, in a White House meeting with Henry Kissinger, he found an enthusiastic proponent for an offensive. Stuart Symington led the general to believe financial backing for the Laotian War would not be curtailed. With this backing, Vang Pao returned to Laos and to his war in Military Region 2.[9]

GM 31 arrived on 2 July, and captured two hills overlooking a new PAVN supply road, Route 54. On 16 July, as GM 30 rotated out of action, GM 31 launched an assault on Phou Phasai from a differing direction. A variety of battalion-size assaults met with no more success.[6]

Operation Phou Phiang II (Operation Plateau II) was planned at Udorn Royal Thai Air Force Base on 26 July 1972. Hmong General Vang Pao met with his two senior CIA advisers and the Thai general in charge of supplying mercenary troops to the "Secret War" in Laos. The tribal leader was worried about the Communist troops' continuing proximity to the guerrilla main base at Long Tieng.[10]

For once, Vang Pao's American backers did not try to discourage a wet season offensive. Planning was based on the assumption that Vang Pao would have at least 11, and possibly 13, regiments available to him by mid-September 1972. By launching five small attacks, it was hoped that the Communist would be too overwhelmed to concentrate on one of them. A two phase plan of attack was formed. Phase one, planned to start on 15 August, would draw PAVN reinforcements southwestward of the Plain of Jars while capturing the mountaintop position at Phou Seu. Then, two regiments of guerrillas would be landed in the vacuum behind the front lines thus caused by the PAVN's forward movement. Phase two would follow on with two road interdictions planned to starve out the PAVN, followed by establishment of an interlocking network of artillery fire bases after the Communists withdrew. Not figured in the Royalist calculations was the determination of PAVN General Vũ Lập to alter Communist policy and maintain PAVN's positions on the Plain through the rainy season monsoon.[8][11]

Vang Pao jumped the gun to begin his operation in early August. He organized his attacking troops into five separate task forces. He struggled to coordinate the start of the task force assaults over the first three weeks in August. By the time Phou Phiang II was a week old, PAVN reactions were not following the Royalist planners' expectations. The offensive was in trouble.[12]

With his assault schedule thrown out of whack by the PAVN, and his troops consequently in trouble, Vang Pao went looking for help. On 1 September, he made an emergency flight to Vientiane for a tense meeting with Ambassador G. McMurtrie Godley at the airfield. Hoping to cadge more air support, the general blamed a shortage of tactical air for the offensive's lack of success. From Godley's standpoint, the Hmong unit commanders left much to be desired for combat leadership of a force crippled by trench foot. The ambassador made it clear that U.S. tactical air support was limited to 18 daily sorties. He then asked if Vang Pao would continue the offensive on those terms. At this, Vang Pao returned to battle, knowing that saving Long Tieng was essential for the Royalists.[13][14]

On 19 September, the CIA station in Vientiane reported to Headquarters in the U.S. that the PAVN were successfully adapting the Hmong guerrilla small unit tactics of harassing opposing troop concentrations. They were trying "not only to blunt Vang Pao's offensive, but to wipe him out...."[15]

A successful first phase had not been included in planning as a prerequisite for the second phase of Phou Phiang II. However, the 1 October announcement of the start of phase two shocked Washington. On 6 October, Vientiane cabled Washington the plans to interdict supply routes running from Vietnam to the Plain of Jars. A reply confirming ongoing U.S. Air Force air support was taken for approval for phase two.[22]

The air support supplied for phase two would include a new weapons system. Operation Sentinel Lock was a combined photo-mapping and navigational emplacement program to enable radar-directed interdiction bombing by F-111s of the 474th Tactical Fighter Wing based in Thailand and B-52s, using a ground-based beacon for targeting guidance. The beacon bombing efforts began supporting Operation Phou Phiang II on 11 November 1972, with the radar guided bombing being especially valuable during foul weather.[23]

Overall, the guerrillas' need for staff coordination of their movements became apparent as a result of this operation as early as 16 September. As it worked out, Communist forces defeated the Royalists in detail.[8]

Task Force Alpha's offensive was stalled by PAVN resistance by 25 August. One of its regiments was subsequently withdrawn for refitting. Basically, the task force never got away from its start point.[18]

Task Force Bravo's three regiments were defeated and in retrograde mode by 26 September. They had to be stabilized by hasty commitment of a regrouped and previously defeated regiment.[19] Task force regiments later were thwarted in capturing two objectives from the PAVN.[24]

In Task Force Charlie, GM 15 scattered while under attack when their CIA adviser was killed on 27 September. Despite this setback, the task force assaulted the PAVN in and around Lat Sen three times during October. As this task force was the only one enjoying any success, its operation was stoked with reinforcements from the reserves and from stalemated columns. GM 32 took 220 dead, 270 wounded, and at least 53 missing; it was left unfit for further combat and withdrawn from the operation. Two Thai battalions were also decimated. GM 30 was defeated and sapped by desertions. GM 15 went on one last offensive, only to plow head-on into the earliest PAVN dry season offensive of the war.[26]

Task Force Delta was plagued by underage, sloppy soldiers. Once five PAVN battalions coalesced upon it, it was defeated by tanks and artillery fire. Of the Task Force Delta regiments, GM 26 mustered at 40% strength when it regrouped back at Long Tieng. Its executive officer and a battalion commander had been killed. GM 21 regrouped independently, in the vicinity of Ban Na. With the task force suffering over 600 cases of trench foot in addition to other casualties, it was finished as a fighting force by 3 September.[13]

Task Force Echo was struck heavily by "friendly" air strikes on both 9 and 16 September, suffering 64 killed and at least 43 wounded. The accidental bombings caused the temporary withdrawal of GM 24. However, whether staffed with one regiment or two, Task Force Echo was stopped by the PAVN after minor harassment of Communist supply Route 71.[27]

As a late and unplanned addition to the operation, Task Force Foxtrot was expected to rampage through the PAVN rear areas north of Ban Ban after it was committed in mid-October. However, a PAVN blocking force stalemated it.[24]

Operation Tulah achieved no perceptible results.[24]

In late October, ceasefire negotiations began for settling the Laotian Civil War as well as the Vietnam War.[28]

In late November, four fresh Thai battalions landed at Long Tieng. Four tired ones rotated out. On 6 December, some of the new arrivals were lifted by Air America into the Nam Bleung Valley to attack a numerically inferior garrison of PAVN troops. They were also directed at Phou Phasai, attacking from both southeast and southwest while backed by GM 21 and GM 26. In this case, the attackers also outnumbered the defenders. In all cases, the Royalist attacks failed.[29]

A peace settlement would freeze the opposing forces in place. The PAVN would be left with positions in uneasy proximity with the Royalist guerrillas at Long Tieng. This would lead to Vang Pao's next move.[28]

• Ahern, Thomas L. Jr. (2006), Undercover Armies: CIA and Surrogate Warfare in Laos. Center for the Study of Intelligence. Classified control no. C05303949.
• Anthony, Victor B. and Richard R. Sexton (1993). The War in Northern Laos. Command for Air Force History, DTIC ADA512223. OCLC 232549943.
• Castle, Timothy N. (1993). At War in the Shadow of Vietnam: U.S. Military Aid to the Royal Lao Government 1955–1975. ISBN 0-231-07977-X.
• Conboy, Kenneth and James Morrison (1995). Shadow War: The CIA's Secret War in Laos. Paladin Press. ISBN 0-87364-825-0.
• Warner, Roger (1995). Back Fire: The CIA's Secret War in Laos and Its Link to the War in Vietnam. Simon & Schuster. ISBN 0-684-80292-9.