The United States has a long and checkered record of attempts to aid anticommunist movements, dating from the onset of the Cold War. Most of the efforts have failed.

The largest efforts of this kind mounted by the Central Intelligence Agency were aimed at Soviet-backed governments or movements in Cuba, Iraq and Angola. None was successful.

The CIA did succeed in engineering coups that installed friendly governments in Iran (1953) and Guatemala (1954), and its aid helped to pave the way for the present government of Chile (1973). It also backed the winning side in the Chadian civil war of 1981-82. Other interventions have been alleged but not documented.

It was characteristic of past efforts to begin supporting an insurgency group only to drop it later as a result of shifting politics at home or changing circumstances abroad.

Washington helped organize Cuban exiles after Fidel Castro came to power in 1959 and launched them on the disastrous Bay of Pigs invasion of Cuba in 1961. Cuban exiles still blame that fiasco on inadequate CIA support.

In the first Nixon administration, the United States gave extensive covert aid to Mustafa Barzani, leader of rebel Kurds fighting for autonomy against the Soviet-backed Iraqi government in Baghdad. With the help of tens of millions of dollars in U.S. assistance channeled through Iran, Barzani marshaled an army he claimed included 100,000 troops.

But when the shah of Iran negotiated a settlement to an old border dispute with Iraq in March 1975, Iran and the United States abruptly cut off their support for Barzani. The decision sent 200,000 to 300,000 Kurds fleeing into Iran, and Barzani accused Washington and Tehran of betrayal. He went into exile and died here in 1978, a bitter and broken man.

In Angola, the United States became deeply involved in the three-way struggle for power among nationalist factions at the time of the former Portuguese colony's independence in 1975. The United States gave principal backing to Holden Roberto, leader of the National Front for the Liberation of Angola (FNLA), and some aid to the National Union for the Total Independence of Angola (UNITA), hoping to block a third faction, backed by Cuba, the Popular Movement for the Liberation of Angola (MPLA).

But the MPLA took the capital. When the extent of U.S. secret involvement in the war became known, Congress voted overwhelmingly in late 1975 to ban military aid to the two pro-western Angolan factions. The FNLA quickly collapsed, but UNITA has survived and grown much stronger, thanks partly to aid from South Africa.

Today, a move is afoot in both houses of Congress to repeal the aid ban in order to help UNITA again.

In Chad, the CIA scored its only recent public success. The agency worked with the intelligence services of Sudan and Egypt to back Hissene Habre in his 1981-1982 struggle against a Libyan-backed government headed by President Goukouni Oueddei. With French help, Habre has remained in power.