Pol Pot resignation seen as a cosmetic change for Khmer Rouge. Kampuchea rebel leader shifts focus to fighting Vietnamese, analysts say

The announcement Monday that Pol Pot, guiding force behind the Khmer Rouge, had resigned came as a big surprise. Even diplomats from the secretive movement's main backers -- China and the Khmer Rouge's non-communist partners in the Coalition Government of Democratic Kampuchea (CGDK) -- were taken aback.

The radio report said that Pol Pot had retired as commander in chief of the Khmer Rouge army and would be replaced by Son Sen, a former deputy premier for defense currently in charge of Khmer Rouge operations in northern and eastern Kampuchea (Cambodia).

The broadcast also announced the abolition of the supreme military council that had formulated Khmer Rouge military strategy.

A variety of explanations, based on conjecture rather than on hard fact, have been put forward for the leadership shuffle. These include that Pol Pot is the victim of illness or a power struggle -- or that the change is simply a clumsy effort to clean up the Khmer Rouge's murderous public image.

The most plausible explanation now is that Pol Pot's retirement is purely cosmetic. Instead of retiring, Pol Pot -- the secretive leader of one of the world's most secretive revolutionary organizations -- may simply have slipped further into the background. There he could concentrate on the war against the Vietnamese and the government they back in Phnom Penh.

Pol Pot's leadership of the Khmer Rouge has been a propaganda bonus to the CGDK's enemies and an embarrassment to its backers.

Between 1975 and 1979, when his Democratic Kampuchean Movement was in power, hundreds of thousands of Khmers died. The movement's image is still a sinister one: It is regularly accused of killing the troops of its own coalition allies, and its battle reports never mention taking Vietnamese prisoners. (The Khmer Rouge's two noncommunist partners in the CGDK are led by Prince Norodom Sihanouk and Son Sann, Sihanouk's former prime minister.)

But some coalition supporters, especially China, have argued forcefully that the removal of Pol Pot would demoralize the Khmer Rouge army -- estimated at something between 35,000 and 45,000 -- and deprive the anti-Vietnamese movement of its most gifted strategist.

The vigor of past Chinese support appears to militate against the theory that Pol Pot has been dropped because of pressure from Peking.

One aspect of the official Khmer Rouge explanation of the leadership change seems to support the cosmetic theory. The official announcement on the clandestine Khmer Rouge radio -- dated Aug. 24, but delayed for over a week -- said the Khmer Rouge had now introduced a mandatory retirement age of 60. Pol Pot, having reached this age (one biography says he was born in 1925, another 1928) was now stepping down. But, the radio continued, he would retain an advisory role as head of a higher institute for nati onal defense.

The choice of a research role for Pol Pot is reminiscent of a tactic that the Vietnamese Communist Party used in 1945. During the tough, early years of the war against the French, the Vietnamese communists announced the party's spurious dissolution. It then continued covertly as the institute for research into Marxism.

Another argument being used for Pol Pot's retirement is ill health. At various times since 1979 he has been reported to be suffering from malaria or a heart condition. On at least one occasion he was reportedly hospitalized in Bangkok.

But Chinese officials who conferred with him earlier this year say he was in good health. In a conversation on the Thai-Khmer border Aug. 28 -- four days after the decision had been made -- one of Pol Pot's closest collaborators, Ieng Sary, told this correspondent that the Khmer Rouge leader was healthy. ``All Khmer Rouge cadres suffer occasionally from malaria,'' Sary said. ``This is just part of jungle life. But Pol Pot is otherwise in good condition.''

The other argument put forward is that Pol Pot has been ousted by Son Sen in a power struggle.

Here the evidence is currently too scanty and confused to evaluate. The Khmer Rouge tendency toward bloody purges is well-documented. During an obscure power struggle in September 1976, Pol Pot withdrew temporarily from the scene, apparently claiming illness. Son Sen himself almost fell victim to a purge in 1978, just before the Vietnamese invaded. But Son Sen has not hitherto been thought to have an independent power base: Pol Pot and Ta Mok, the top Khmer Rouge military commander, have been considered

more powerful and influential.

Ta Mok apparently has at least lost his position in the now defunct supreme military council. He was also badly wounded last year. But diplomats who met him earlier this year say he is still fit and active. Any change in Ta Mok's position -- as commander of the most important Khmer Rouge military area -- would help clarify the mystery.

But for the time being, Son Sen is believed to be no more ``moderate'' than Pol Pot.

He and Pol Pot have been together since the beginning, when they both were students in France and in 1963 fled together with Ieng Sary to form the nucleus of the present Khmer Rouge leadership. During the years of power in Phnom Penh, Son Sen controlled what is called ``S21,'' the regime's security and torture apparatus. S21 was therefore directly or indirectly responsible for hundreds of thousands of deaths.

In the final analysis, although the Vietnamese and the Heng Samrin regime they back in Phnom Penh have recently been calling for Pol Pot's ``elimination,'' the latest move will satisfy neither Hanoi nor Phnom Penh. Both say they want to see not just the removal of Pol Pot the individual, but the elimination of his political and military organization. The latest move has obviously been made in the hope of improving -- not dismantling -- it.