Due to the ostensible neutrality of Laos, guaranteed by the Geneva Conference of 1954 and 1962, both the U.S. and North Vietnam strove to maintain the secrecy of their operations and only slowly escalated military actions there.

[5]: 72  Despite another international accord, Laos remained ensnared by the political and territorial ambitions of communist neighbors, the security concerns of Thailand and the United States, and geographic fate.

Although tentative negotiations resumed between the factions, matters took a turn for the worse when neutralist Prime Minister Prince Souvanna Phouma was arrested during a right-wing coup attempt.

[7] In November 1963 General Maxwell D. Taylor, chairman of the Joint Chiefs of Staff had proposed that U.S. armed reconnaissance missions be conducted over Laos as part of a two phase program that would warn Hanoi of U.S. determination to support the Saigon government.

The mission of the USAF was to seal off the southern Mekong River Valley, thus providing a buffer for Thailand; insulating the Vientiane government from direct communist threat; draining PAVN manpower and resources; and interdiction of the approaches to the Ho Chi Minh trail.

The next stage of the military evolution took place during mid-March 1964, when the USAF began Project Waterpump, a program to train Laotian, Thai, Hmong, and Air America aircrews in flight and maintenance of U.S.-supplied AT-28 Trojan ground-attack aircraft.

He had to balance the competing interests of the CIA, the Seventh Air Force, MACV and the Thais, and this had to be done without alienating Souvanna Phouma, an ally in all but name who acquiesced to almost every U.S. action within his country, short of outright invasion.

Barrel Roll was to continue in the northeast while the southern portion of the area, where interdiction missions against the Ho Chi Minh trail were paramount, was redesignated Tiger Hound.

It was decided at the Honolulu Executive Conference of April 1965 that U.S. aircraft could be used for interdiction in Laos only after close air support needs were met in South Vietnam.

[14]: 168–9 Hmong forces, PAVN, and Pathet Lao fought to control the strategic Plain of Jars, a 500 square miles (1,300 km2) plateau north and northeast of Vientiane, covered with grass and small hills.

Electronic tactical air navigation (TACAN) became an necessity in Laos, where mountain peaks and unexpected bad weather made flying extremely hazardous, especially for older aircraft.

This problem was solved by establishing unmanned Air Force stations that broadcast continuous radio transmissions, allowing aerial navigation from fixed geographic reference points.

Pagodas and suspected PAVN hospitals (which were unmarked) were simply turned into ammunition dumps, supply caches, and anti-aircraft sites by an enemy that intently studied American actions and adjusted to them.

In the panhandle, the Laotian garrison at Ban Houi Sane, along Route 9 and 21 miles (34 km) west of the U.S. Marines' Khe Sanh Combat Base, was overrun by the PAVN 24th Regiment, 314th Division supported by Soviet-built PT-76 tanks.

[22] Further south, PAVN Group 565 advanced in Khammouane Province, seizing the rice harvest and placing themselves in position to overrun the cities of Saravane and Attopeu with little forewarning.

Two Soviet-built An-2 Colt biplanes of the North Vietnamese Vietnam People's Air Force attacked Lima Site 85 atop a craggy peak known as Phou Pha Thi.

Regardless, the PAVN launched Campaign Thoan Thang (Total Victory) during late June and managed to take Muang Soui with the assistance of armoured units.

[21]: 211–3 In June, William Sullivan was replaced as ambassador by G. McMurtrie Godley, who immediately loosened the rules of engagement and increased the bombing campaign in the north and northeast.

[11]: 46 On 6 August 1969, in Military Region 2, Hmong forces launched a major counterattack, the Kou Kiet (Redeem Honor) Campaign, against the communists on the Plain of Jars and in the Xieng Kouang area, supported by its own air units and the USAF.

[25] By February they had occupied the entire Plain of Jars, Long Tieng had been surrounded, and, for the first time since 1962, Pathet Lao forces were camped within sight of the royal capital of Luang Prabang.

Previously during the conflict, air mobility by STOL aircraft into the Lima Sites had provided the Hmong with an advantage over the road-bound PAVN and Pathet Lao forces.

The American command in Saigon and the politicians in Washington were opposed to a wet season Hmong offensive, supporting instead a holding action on the edge of the Plain of Jars as a prelude to a possible cease-fire.

President Richard M. Nixon was eventually forced to disclose the extent of U.S. participation, which further weakened ability of the U.S. to respond to the increasing PAVN and Pathet Lao threat.

[21]: 249 In March 1971 South Vietnamese forces, supported by U.S. air power, launched Operation Lam Son 719, the long-awaited offensive to cut the Ho Chi Minh trail in southeastern Laos.

In November 1969, he tried a different tack, contacting the Pathet Lao and attempted to negotiate a quid pro quo: the Hmong would cease fighting if the communists would allow them to establish a semiautonomous state in Xieng Khouang Province.

The launching of PAVN's Nguyen Hue Offensive in April 1972 had the effect of returning major American air assets to the theater and eventually increased the tempo of operations in northeastern Laos.

That the North Vietnamese would uphold it, after violating two previous neutrality accords, "took optimism bordering on an act of faith that they would now abandon the ambitions and struggles of thirty years because of a clumsily drafted afterthought in a document they had no intention of honoring anyway.

[25]: 272  Once again acceding to a request from Souvanna, B-52s returned for two more days of bombing on 16 and 17 April, dropping ordnance in support of government forces under attack around Ban Tha Vieng on the Plain of Jars.

It had allowed the continuous prosecution of the Steel Tiger (and, post-1968, Operation Commando Hunt) interdiction campaigns against the Ho Chi Minh trail by keeping the neutralists in power.

[10]: 37  The imposition of a strategic stalemate had prevented the fall of the Vientiane government, which accomplished the secondary goal of the operation, protecting Thailand from communist attack (however unrealistic that threat appears today).