Found this on the web, will try to retrace provenance, worth a read: The United States have a well known history of providing military support to countries in need. But from time to time, the US Government has provided secret forces. While many are successful, there have also been a number of failures. This is a list of the ten top secret armies of the CIA.

1. Ukrainian Partisans
From 1945 to 1952 the CIA trained and aerially supplied Ukranian partisan units which had originally been organised by he Germans to fight the Soviets during WWII. For seven years, the partisans, operating in the Carpathian Mountains, made sporadic attacks. Finally in 1952, a massive Soviet military force wiped them out.

2. Chinese Brigade in Burma
After the Communist victory in China, Nationalist Chinese soldiers fled into northern Burma. During the early 1950s, the CIA used these soldiers to create a 12,000 man brigade which made raids into Red China. However, the Nationalist soldiers found it more profitable to monopolise the local opium trade.

3. Guatemalan Rebel Army
After Guatemalan president Jacobo Arbenz legalised that country’s communist party and expropriated 400,000 acres of United Fruit banana plantations, the CIA decided to overthrow his government. Guatemalan rebels were trained in Honduras and backed up with a CIA air contingent of bombers and fighter planes. This army invaded Guatemala in 1954, promptly toppling Arbenz’s regine.

4. Sumatran Rebels
In an attempt to overthrow Indonesian president Sukarno in 1958, the CIA sent paramilitary experts and radio operators to the island of Sumatra to organise a revolt. With CIA air support, the rebel army attacked but was quickly defeated. The American government denied involvement even after a CIA b-26 was shot down and its CIA pilot, Allen Pope, was captured.

5. Khamba Horsemen
After the 1950 Chinese invasion of Tibet, the CIA began recruiting Khamba horsemen – fierce warriors who supported Tibet’s religious leader, the Dalai Lama – as they escaped into India in 1959. These Khambas were trained in modern warfare at Camp Hale, high in the rocky mountains near Leadville, Colorado. Transported back to Tibet by the CIA operated Air American, the Khambas organised an army number at its peak some 14,000. By the mid-1960s the Khambas had been abandoned by the CIA but they fought on alone until 1970.

6. Bay of Pigs Invasion Force
In 1960, CIA operatives recruited 1,500 Cuban refugees living in Miami and staged a surprise attack on Fidel Castro’s Cuba. Trained at a base in Guatemala, this small army – complete with an air force consisting of B-26 bombers – landed at the Bay of Pigs on April 19, 1961. The ill-conceived, poorly planned operation ended in disaster, since all but 150 men of the force were either killed or captured within three days.

7. L’armee Clandestine
In 1962, CIA agents recruited Meo tribesmen living in the mountains of Laos to fight as guerrillas against Communist Pathet Lao forces. Called l’armee Clandestine, this unit – paid, trained, and supplied by the CIA – grew into a 30,000 man force. By 1975 the Meos – who had numbers a quarter million in 1962 – had been reduced to 10,000 refugees fleeing into Thailand.

8. Nung Mercenaries
A Chinese hill people living in Vietname, the Nungs were hired and organised by the CIA as a mercenary force, during the Vietnam war. Fearsome and brutal fighters, the Nungs were employed throughout Vietnam and along the Ho Chi Minh Trail. The Nungs proved costly since they refused to fight unless constantly supplied with beer and prostitutes.

9. Peruvian Regiment
Unable to quell guerrilla forces in its eastern Amazonian provinces, Peru called on the US for help in the mid-1960s. The CIA responded by establishing a fortified camp in the area and hiring local Peruvians who were trained by Green Beret personnel on loan from the US army. After crushing the guerrillas, the elite unit was disbanded because of fears it might stage a coup against the government.

10. Congo Mercenary Force
In 1964, during the Congolese Civil War, the CIA established an army in the Congo to back pro-Western leaders Cyril Adoula and Joseph Mobutu. The CIA imported European mercenaries and Cuban pilots – exiles from Cuba – to pilot the CIA air force, composed of transports and B-26 Bombers.

11. The Cambodian Coup
For over 15 years, the CIA had tried various unsuccessful means of deposing Cambodia’s left-leaning Prince Norodom Sihanouk, including assassination attempts. However, in March, 1970, a CIA-backed coup finally did the job. Funded by US tax dollars, armed with US weapons, and trained by American Green Berets, anti-Sihanouk forces called Kampuchea Khmer Krom (KKK) overran the capital of Phnom Penh and took control of the government. With the blessing of the CIA and the Nixon administration, control of Cambodia was placed in the hands of Lon Nol, who would later distinguish himself by dispatching soldiers to butcher tens of thousands of civilians.

12. Kurd Rebels
During the early 1970s the CIA moved into eastern Iraq to organize and supply the Kurds of that area, who were rebelling against the pro-Soviet Iraqi government. The real purpose behind this action was to help the shah of Iran settle a border dispute with Iraq favourably. After an Iranian-Iraq settlement was reached, the CIA withdrew its support from the Kurds, who were then crushed by the Iraqi Army.

13. Angola Mercenary Force
In 1975, after years of bloody fighting and civil unrest in Angola, Portugal resolved to relinquish its hold on the last of its African colonies. The transition was to take place on November 11, with control of the country going to whichever political faction controlled the capital city of Luanda on that date. In the months preceding the change, three groups vied for power: the Popular Movement for the Liberation of Angola (MPLA), the National Front for the Liberation of Angola (FNLA) and the National Union for the Total Independence of Angola (UNITA). By July 1975, the Marxist MPLA had ousted the moderate FNLA and UNITA from Luanda, so the CIA decided to intervene covertly. Over $30 million was spent on the Angolan operation, the bulk of the money going to buy arms and pay French and South African mercenaries, who aided the FNLA and UNITA in their fight. Despite overwhelming evidence to the contrary, US officials categorically denied any involvement in the Angolan conflict. In the end, it was a fruitless military adventure, for the MPLA assumed power and controls Angola to this day.

14. Afghan Mujaheedin
Covert support for the groups fighting against the Soviet invasion of Afghanistan began under President Jimmy Carter in 1979, and was stepped up during the administration of Ronald Reagan. The operation succeeded in its initial goal, as the Soviets were forced to begin withdrawing their forces in 1987. Unfortunately, once the Soviets left, the US essentially ignored Afghanistan as it collapsed into a five-year civil war followed by the rise of the ultra-fundamentalist Taliban. The Taliban provided a haven for Osama bin Laden and al-Qaeda, the perpetrators of the 9/11 terrorist attacks in 2001.

15. Salvadoran Death Squads
As far back as 1964, the CIA helped form ORDEN and ANSESAL, two paramilitary intelligence networks that developed into the Salvadoran death squads. The CIA trained ORDEN leaders in the use of automatic weapons and surveillance techniques, and placed several leaders on the CIA payroll. The CIA also provided detailed intelligence on Salvadoran individuals later murdered by the death squads. During the civil war in El Salvador from 1980 to 1992, the death squads were responsible for 40,000 killings. Even after a public outcry forced President Reagan to denounce the death squads in 1984, CIA support continued.

16. Nicaraguan Contras
On November 23, 1981, President Ronald Reagan signed a top secret National Security Directive authorising the CIA to spend $19 million to recruit and support the Contras, opponents of Nicaragua’s Sandinista government. In supporting the Contras, the CIA carried out several acts of sabotage without the Congressional intelligence committees giving consent – or even being informed beforehand. In response, Congress passed the Boland Amendment, prohibiting the CIA from providing aid to the Contras. Attempts to find alternate sources of funds led to the Iran-Contra scandal. It may also have led the CIA and the Contras to become actively involved in drug smuggling. In 1988, the Senate Subcommittee on Narcotics, Terrorism, and International Operations concluded that individuals in the Contra movement engaged in drug trafficking; that known drug traffickers provided assistance to the Contras; and that ‘there are some serious questions as to whether or not US officials involved in Central America failed to address the drug issue for fear of jeopardizing the war effort against Nicaragua’.

17. Haitian Coup
In 1988, the CIA attempted to intervene in Haiti’s elections with a ‘covert action program’ to undermine the campaign of the eventual winner, Jean-Bertrand Aristide. Three years later, Aristide was overthrown in a bloody coup that killed more than 4,000 civilians. Many of the leaders of the coup had been on the CIA payroll since the mid-1980s. For example, Emmanuel ‘Toto’ Constant, the head of FRAPH, a brutal gang of thugs known for murder, torture, and beatings, admitted to being a paid agent of the CIA. Similarly, the CIA-created Haitian National Intelligence Service (NIS), supposedly created to combat drugs, functioned during the coup as a ‘political intimidation and assassination squad.’ In 1994, an American force of 20,000 was sent to Haiti to allow Aristide to return. Ironically, even after this, the CIA continued working with FRAPH and the NIS. In 2004, Aristide was overthrown once again, with Aristide claiming that US forces had kidnapped him.

18. Venezuelan Coup Attempt
On April 11, 2002, Venezuelan military leaders attempted to overthrow the country’s democratically-elected left-wing president, Hugo Chavez. The coup collapsed after two days as hundreds of thousands of people took to the streets and as units of the military joined with the protestors. The administration of George W. Bush was the only democracy in the Western Hemisphere not to condemn the coup attempt. According to intelligence analyst Wayne Madsen, the CIA had actively organised the coup: ‘The CIA provided Special Operations Group personnel, headed by a lieutenant colonel on loan from the US Special Operations Command at Fort Bragg, North Carolina, to help organise the coup against Chavez.