
The K5 Plan (), K5 Belt or K5 Project, also known as the Bamboo Curtain, was an attempt between 1985 and 1989 by the government of the
People's Republic of Kampuchea
The People's Republic of Kampuchea (PRK) was a partially recognised state in Southeast Asia which existed from 1979 to 1989. It was a satellite state of Vietnam, founded in Cambodia by the Vietnamese-backed Kampuchean United Front for Nationa ...
to seal
Khmer Rouge
The Khmer Rouge is the name that was popularly given to members of the Communist Party of Kampuchea (CPK), and by extension to Democratic Kampuchea, which ruled Cambodia between 1975 and 1979. The name was coined in the 1960s by Norodom Sihano ...
guerrilla infiltration routes into
Cambodia
Cambodia, officially the Kingdom of Cambodia, is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. It is bordered by Thailand to the northwest, Laos to the north, and Vietnam to the east, and has a coastline ...
by means of trenches, wire fences, and
minefield
A land mine, or landmine, is an explosive weapon often concealed under or camouflaged on the ground, and designed to destroy or disable enemy targets as they pass over or near it. Land mines are divided into two types: anti-tank mines, wh ...
s along virtually the entire
Cambodia–Thailand border.
[Margaret Slocomb, ''The People's Republic of Kampuchea, 1979-1989: The revolution after Pol Pot'' ]
Background

After the defeat of
Democratic Kampuchea in 1979, the
Khmer Rouge
The Khmer Rouge is the name that was popularly given to members of the Communist Party of Kampuchea (CPK), and by extension to Democratic Kampuchea, which ruled Cambodia between 1975 and 1979. The name was coined in the 1960s by Norodom Sihano ...
fled Cambodia quickly. Protected by the Thai state, and with powerful foreign connections,
Pol Pot
Pol Pot (born Saloth Sâr; 19 May 1925 – 15 April 1998) was a Cambodian politician, revolutionary, and dictator who ruled the communist state of Democratic Kampuchea from 1976 until Cambodian–Vietnamese War, his overthrow in 1979. During ...
's virtually intact militia of about 30,000 to 35,000 troops regrouped and reorganized in forested and mountainous zones behind the Thai-Cambodian border. During the early 1980s Khmer Rouge forces showed their strength in
Thailand
Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...
, inside the refugee camps near the border, and were able to receive a steady and abundant supply of military equipment. The weapons came mainly from China and the US and were channeled across Thailand with the cooperation of the
Royal Thai Armed Forces
The Royal Thai Armed Forces (RTARF; ; ) are the armed forces of the Kingdom of Thailand.
The Highest Commander of the Royal Thai Armed Forces (จอมทัพไทย; ) is the King of Thailand. The armed forces are managed by the Minist ...
.
[Puangthong Rungswasdisab, ''Thailand's Response to the Cambodian Genocide''](_blank)
/ref>
From their position of security in hidden military outposts along the Thai border, the Khmer Rouge militias launched a relentless military campaign against the newly established People's Republic of Kampuchea state. Even though the Khmer Rouge was dominant, it fought against the Kampuchean People's Revolutionary Armed Forces (KPRAF) and Vietnam People's Army along with minor non-communist armed factions which had formerly been fighting against the Khmer Rouge between 1975 and 1979.
The border war followed a wet season
The wet season (sometimes called the rainy season or monsoon season) is the time of year when most of a region's average annual rainfall occurs. Generally, the season lasts at least one month. The term ''green season'' is also sometimes used a ...
/ dry season
The dry season is a yearly period of low rainfall, especially in the tropics. The weather in the tropics is dominated by the tropical rain belt, which moves from the northern to the southern tropics and back over the course of the year. The t ...
rhythm. Generally, the heavily armed Vietnamese forces conducted offensive operations during the dry seasons, and the Chinese-backed Khmer Rouge held the initiative during the rainy seasons. In 1982, Vietnam launched a largely unsuccessful offensive against the main Khmer Rouge base at Phnom Malai in the Cardamom Mountains
The Cardamom Mountains (, ; , ), or the Krâvanh Mountains, is a mountain range in the southwest part of Cambodia and Eastern Thailand. The majority of the range is within Cambodia.
The silhouette of the Cardamom Mountains appears in the Sea ...
.
The major consequence of the border civil war was that the PRK was hampered in its efforts to rebuild the much-damaged nation and consolidate its administration. The new republic's rule was tenuous in the border areas owing to persistent sabotage by the Khmer Rouge of the provincial administrative system through constant guerrilla warfare.
Implementation
The architect of the K5 plan was Vietnamese general Lê Đức Anh
Lê Đức Anh (; 1 December 1920 – 22 April 2019) was a Vietnamese politician and general who served as the fifth President of Vietnam from 1992 to 1997. He previously led the Vietnamese forces in Cambodia throughout the 1980s. He was regar ...
, commander of the PAVN forces in Cambodia. He formulated five key points for the defence of Cambodia against Khmer Rouge re-infiltration. Letter "K", the first letter of the Khmer alphabet, came from ''kar karpier'', meaning 'defence' in the Khmer language
Khmer ( ; , Romanization of Khmer#UNGEGN, UNGEGN: ) is an Austroasiatic language spoken natively by the Khmer people. This language is an official language and national language of Cambodia. The language is also widely spoken by Khmer people i ...
, and number "5" referred to Le Duc Anh's five points in his plan of defence, of which the sealing of the border with Thailand
Thailand, officially the Kingdom of Thailand and historically known as Siam (the official name until 1939), is a country in Southeast Asia on the Mainland Southeast Asia, Indochinese Peninsula. With a population of almost 66 million, it spa ...
was the second point. Many workers on the project, however, did not know what "K5" stood for.
The K5 Plan began on 19 July 1984. It became a gigantic effort that included clearing long patches of tropical forest
Tropical forests are forested ecoregions with tropical climates – that is, land areas approximately bounded by the Tropic of Cancer, tropics of Cancer and Tropic of Capricorn, Capricorn, but possibly affected by other factors such as prevailing ...
by felling a great number of trees, as well as slashing and uprooting tall vegetation.
The purpose was to leave a continuous broad open space all along the Thai border that would be watched and mined.
In practice the K5 fence consisted of a roughly 700 km-long, 500 m-wide swath of land along the border with Thailand, where antitank and antipersonnel mines were buried to a density of about 3,000 mines per kilometre of frontage.
Consequences
From the environmental viewpoint the massive felling of trees was an ecological disaster, contributing to acute deforestation
Deforestation or forest clearance is the removal and destruction of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. Ab ...
, the endangerment of species, and leaving behind a vast degraded area. The more remote places, like the Cardamom Mountains
The Cardamom Mountains (, ; , ), or the Krâvanh Mountains, is a mountain range in the southwest part of Cambodia and Eastern Thailand. The majority of the range is within Cambodia.
The silhouette of the Cardamom Mountains appears in the Sea ...
had been relatively untouched by man until they became a stronghold of the Khmer Rouge in the 1980s. Presently these mountains are an endangered ecoregion
An ecoregion (ecological region) is an ecological and geographic area that exists on multiple different levels, defined by type, quality, and quantity of environmental resources. Ecoregions cover relatively large areas of land or water, and c ...
.
Unforeseen by the planners of the project, from the military point of view the K5 Plan was also disastrous for the PRK. It did not deter the Khmer Rouge fighters who found ways to cross it, for it was impossible to effectively police the long border. Besides, maintenance was difficult, as the razed jungle left a scruffy undergrowth that, in the tropical climate, would grow again yearly to about a man's height.[Soizick Crochet, ''Le Cambodge'', Karthala, Paris 1997, ]
The K5 Plan was counterproductive for the image of the PRK, as a republic bent on reconstructing what the rule of Pol Pot and his Communist Party of Kampuchea had destroyed in Cambodia. Despite the magnitude of the effort, the whole project was ultimately unsuccessful and ended up playing into the hands of the enemies of the new pro-Hanoi
Hanoi ( ; ; ) is the Capital city, capital and List of cities in Vietnam, second-most populous city of Vietnam. The name "Hanoi" translates to "inside the river" (Hanoi is bordered by the Red River (Asia), Red and Black River (Asia), Black Riv ...
republic. Thousands of Cambodian peasants, who despite the Vietnamese invasion had welcomed their release from the Khmer Rouge's interference in traditional farming and the absence of taxes under the PRK government, became disgruntled.
They were angry at having to abandon their farms in order to dedicate time to clear the jungle, heavy toil they perceived as useless and unfruitful. Their resentment grew in time as they perceived the forced labor to be, albeit without the killings, very similar to what they had experienced under the Khmer Rouge.[Margaret Slocomb, "The K5 Gamble: National Defence and Nation Building under the People's Republic of Kampuchea", ''Journal of Southeast Asian Studies'' (2001), 32 : 195-210 Cambridge University Press] Owing to unsanitary conditions and the abundance of mosquitoes
Mosquitoes, the Culicidae, are a family of small flies consisting of 3,600 species. The word ''mosquito'' (formed by '' mosca'' and diminutive ''-ito'') is Spanish and Portuguese for ''little fly''. Mosquitoes have a slender segmented body, ...
in areas of difficult access, badly fed and badly lodged workers on the K5 project fell victim to malaria
Malaria is a Mosquito-borne disease, mosquito-borne infectious disease that affects vertebrates and ''Anopheles'' mosquitoes. Human malaria causes Signs and symptoms, symptoms that typically include fever, Fatigue (medical), fatigue, vomitin ...
and exhaustion.
Many of the mines remain to this day, making the vast area dangerous. The K5 zone became part of the great landmine problem in Cambodia after the end of the civil war. In 1990 alone, the number of Cambodians that had a leg or foot amputated as a result of an injury caused by a land mine reached around 6,000.NewScientist - "The killing minefields of Cambodia"
/ref>
See also
* People's Republic of Kampuchea
The People's Republic of Kampuchea (PRK) was a partially recognised state in Southeast Asia which existed from 1979 to 1989. It was a satellite state of Vietnam, founded in Cambodia by the Vietnamese-backed Kampuchean United Front for Nationa ...
* Kampuchean People's Revolutionary Armed Forces
* Vietnamese border raids in Thailand
References
Further reading
* Evan Gottesmann, ''Cambodia After the Khmer Rouge: Inside the Politics of Nation Building'',
External links
Comment on Esmeralda Luciolli, ''Le mur de bambou, ou le Cambodge après Pol Pot.''
{{in lang, fr
Sok Udom Deth, ''The Geopolitics of Cambodia During the Cold War Period'', Ohio University
People's Republic of Kampuchea
Fortification lines
Deforestation
Minefields
Environmental disasters in Asia
Cambodia–Thailand border
Hun Sen
Cambodian–Vietnamese War
Military scandals