ON THE DAY AFTER Leonid Brezhnev died, the back page of The New York Times carried a huge advertisement that exulted, "We told America about the death of President Brezhnev before most of Russia learned of it." The advertisement, placed by Satellite News Channel, promised: "Give us eighteen minutes. We'll give you the world."

The flood of instant information in the world today -- at least in the Western industrialized world -- sometimes seems not to further but to retard education; not to excite, but to dampen curiosity; not to enlighten, but merely to dismay. The poet Archibald MacLeish once noted, "We are deluged with facts but we have lost or are losing our human ability to feel them."

The exiled Czech writer Milan Kundera pointed out in "The Book of Laughter and Forgetting" that "the bloody massacre in Bangladesh quickly covered the memory of the Russian invasion of Czechoslovakia; the assassination of (the late Childean President Salvador) Allende drowned out the groans of Bangladesh; the war in the Sinai desert made people forget Allende; the Cambodian massacre made people forget Sinai; and so on and so forth, until ultimately everyone lets everything be forgotten."

I have just finished a book which uses the suffering in Cambodia after the Khmer Rouge came to power to examine the way the world responds to major disasters caused by human actions. The mass killings and terror spread by the regime of Khmer Rouge leader Pol Pot precipitated famine and made refugees out of hundreds of thousands of innocent people. I wanted to try to understand how propaganda affects the "quality of mercy" provided in such a modern catastrophe. And I wanted to explore a little the extent to which the memory of the Holocaust has affected ouperception and imagination when we hear distant cries for help.

In Milan Kundera's vision, the destruction of memory is both the function and the aim of totalitarianism. He is correct -- and for pointing it out the Czechoslovak regime "forgot" him -- he was deprived of his citizenship. But memory is being destroyed in democratic societies as well. Our sense of impotence seems to grow in direct proportion to the spread of our knowledge. And so, in self-protection, does our sense of indifference, or at least our ability to recall, to identify.

Who among us is aware that between 1979 and 1982 six new wars began in the world and only two ended, or that 4 million people and 45 nations were engaged in combat that killed unnumbered millions? And who among us, being aware, knows how to utilize that knowledge?

In 1981, during the week in which there were reports of 8,000 dead in an Iranian earthquake, newspapers and television in the West were consumed in reporting the attempts to rech a small boy who had fallen down a well in Southern Italy. The earthquake was another in the long litany of catastrophes, in which personal involvements were so hard to feel.

At the same time, however, there is an arbitrary and often capricious imbalance in what facts we know. Some areas of the world are bathed in the glare of publicity; from some there are only glimmers of light; others are in total darkness.

The problem results from more than just the speed and selectivity of modern communications. In his book "Language and Silence," George Steiner wonders about the "time relation" of events. While Jews were being murdered in Treblinka "the overwhelming plurality of human beings, two miles away on Polish farms, 5,000 miles away in New York, were sleeping or eating or going to a film or making love or worrying about the dentist. This is where my imagination balks. The two orders of simultaneous experience are so different, so irreconcilable to any common norm of human values, their coexistence is so hideous a paradox -- Treblinka is both because some men have built it, and almost all other men have let it be -- that I puzzle over time.

"Are there, as science fiction and Gnostic speculation imply, different species of time in the same world, 'good times' and enveloping folds of inhuman time in which men fall into the slow hands of living damnation?"

When does a disaster become "Disaster"? How is it that bad news can be long ignored and then suddenly reach such a state of critical mass as to become an international cause celebre?

In April 1945, a correspondent of The Times of London reached the German concentration camp Belsen and wrote: "It is my duty to describe something beyond the imagination of mankind." The news from Belsen, from Dachau, from Auschwitz was a tremendous shock when it was broadcast around the world in 1945. Yet its essence was hardly new.

There were reasons why the early reports of extermination camps and the murder of Jews were hard to accept. The first was that allied propaganda in World War I had been filled with lies; it had tried, often successfully, to persuade people that the Germans were carrying out widespread massacres of civilians, that Belgian babies were being slaughtered and turned into soap, and so on.

In March 1916, the London Daily Telegraph reported that 700,000 Serbs had been gassed to death. The report was widely believed. But it was untrue, and its untruth was subsequently revealed. In June 1942, it was the Daily Telegraph that first reported the massive gassing of the Jews. This time the story was not widely believed. Similarly, propaganda, the fear of propaganda and the excuse of propaganda all played their part when stories of atrocities committed by the Khmer Rouge in Cambodia began to reach the West.

The first accounts began to appear in the Western press in the summer of 1975. In London, early reports were by Bruce Loudoun and John McBeth in the conservative Daily Telegraph. In July, Henry Kamm wrote a long article in The New York Times and the paper ran an editorial comparing the Khmer Rouge policies with "Soviet extermination of kulaks or with the Gulag Archipelago."

Clearly, Cambodia was not ignored. Its travails received far more attention than those of, say, East Timor, Burundi or the Central African Republic, to mention just three other contemporary disasters. Nonetheless, it was some time before many reporters came to accept that terrible events were taking place in Cambodia, or governments in either East or West would acknowledge the truth.

At the end of 1975, for example, Newsweek magazine published a story that cast doubt on the atrocity stories. Early in 1976, The Sunday Times of London did the same. At the end of 1975, I visited China, which was emerging as the one foreign country to develop close ties with the government of Democratic Kampuchea, as the Khmer Rouge had renamed Cambodia. In Peking, a deputy foreign minister assured me blandly that the refugee stories were meaningless and that all was well under the new revolutionary leadership.

In February 1976, Le Monde published a series of articles by a French priest, Francois Ponchaud, which were the first serious attempt to describe and analyze what was taking place in Cambodia. Through 1976 and 1977, and especially in 1978, the Western press's coverage of Cambodia increased. Nevertheless, the issue never reached critical mass. I did not write enough myself and there was no broad campaign in the West as there was, say, over abuses of human rights in Chile.

One reason was the skepticism, to use a mild word, displayed by the Western left. That skepticism was most fervently and frequently expressed by Noam Chomsky, the linguistic philosopher at the Massachusetts Institute of Technology. He asserted that from the moment of the Khmer Rouge victory in 1975 the Western press colluded with Western and anticommunist Asian governments, notably Thailand, to produce a "vast and unprecedented" campaign of propaganda against the Khmer Rouge. Many left-wing journalists and academics took the same line.

The Washington-based pressure group Indochina Resource Center, which had determinedly opposed the American war effort, now threw itself energetically into the defense of the Khmer Rouge against what it saw as vicious calumny in the media.

The government of Vietnam took a long time to denounce the Khmer Rouge. So long as there was a chance of negotiating a settlement with Phnom Penh over borders and other matters, Vietnamese spokesmen continually disregarded stories of Khmer Rouge atrocities told by refugees in Thailand. Throughout the period, the Soviet and East European press published articles favorable to the Khmer Rouge and gave no credence to the refugee reports.

One might have expected the United States government to exploit the stories of horro told by refugees from Cambodia, and to argue that they gave ex post facto justification of the U.S. adventure in Indochina. Americans had, after all, predicted a "bloodbath" if the communists won. But that was not the case.

Strategic considerations -- particularly the importance that was being attached in Washington to the views of both China and the Association of Southeast Asian Nations -- seem to have discouraged the U.S. government and other Western nations from leading any propaganda campaign against the Khmer Rouge between 1975 and 1978. In Bangkok, I found that the U.S. Embassy was surprisingly reluctant to help reporters discover what was going on under the Khmer Rouge, and still less to share information.

The book I wrote took me far longer than I had intended. I found it hard to balance criticism of specific actions of the humanitarian organizations with the assertion that their work is essential.

When Vietnam invaded Cambodia and seized control of the country at the end of 1978, driving the Khmer Rouge into forest retreats on both sides of the border with Thailand, the moral dilemmas of the relief agencies and the Western governments supporting them began. What is a relief agency to do when it knows for certain that some of the food it is supplying to feed refugees is being diverted to sustain the remnants of a barbaric, immoral government -- that of Pol Pot and his Khmer Rouge? Is aid "humanitarian" when it ultimately helps to prolong a political stalemate that, in itself, spreads suffering and misery?

In the aftermath of the Cambodian atrocities, almost all sides exploited humanitarianism to hide the ruthlessness or poverty of their diplomacy. Humanitarian aid was used to build up the Vietnamese regime in Phnom Penh and to rebuild the Khmer Rouge, which the Vietnamese had overthrown. It thus served to consolidate an agonizing political deadlock.

In the fall of 1979, after long years of disaster, Cambodia finally achieved "critical mass" in Western conscience. That it deserved great attention is beyond dispute. But the real needs of the country were often obscured by propaganda, by sensationalism and by cliche, as well as by straight-forward political controls.

As a result, much of the aid was misdirected, much of it was inappropriate, and the Cambodian people as a whole did not benefit from the widespread surge of compassion on their behalf to anything like the extent they deserved.

At one point in my research I asked Brian Urquhart, one of the Secretary General's most experienced assistants at the United Nations, to introduce me to the U.N. Historical Office. He laughed and said that in that whole vast building with its hundreds of offices, there was no room for such a place. "There is no historian at the United Nations, because no two members here could possibly agree on what has happened, let alone on what should be recorded."

At the same time it occurred to me that the fragile state of so much of the world today makes it invidious to concentrate, as I have done, on one particular crisis. The "disasters" which do attract our attention are by no means always the most destructive. Jim Grant, the Executive Director of UNICEF (the United Nations Children's Fund), frequently speaks of the danger of what he calls "loud emergencies" -- like Cambodia -- drowning out the continuous "quiet emergencies" -- like the death of at least 10 million children every year from "causes associated with malnutrition."

The International Committee of the Red Cross calculates that about 30,000 children starved to death in Angola in 1982, and no one noticed. A large majority of the world's people live always in conditions which can only be called "disastrous," yet they are given only minimal aid. In the fall of 1983, Oxfam (the Oxford Committee for Famine Relief) warned that freak weather conditions had brought unprecedented dought to over 40 countries in Asia and Latin America. Oxfam, together with other agencies, warned that unless a huge rescue operation was mounted, agriculture could collapse across a broad swath of the world from Peru through Africa and Asia to the Philippines. But although this disaster might prove catastrophic for scores of Third World societies, it was having little impact upon jaded Western consciousness.

This is not in any way to disparage or diminish the contribution of the people and organizations who tried to help the Cambodian people. The story of Cambodia, as of Biafra in 1968-69, demonstrates that despite the overflow of information to which we are now subjected -- the fast succession of awful images -- the world can still respond. We can still know with the heart as well as the head. The dangers are that we do not always respond when response is most needed, and that propaganda is now able so much more easily to exploit our compassion for uncompassionate ends.

The Nazi war crimes trials at Nuremberg embodied the rhetoric of progress, but they were even at the time tinged at best with irony, at worst with warning, if only because of the ambiguous record of the prosecuting powers, particularly the Soviet Union. It is understandable that the judgment of Nuremberg should have been grasped, in the words of the British writer Rebecca West, as "a sort of legalistic prayer that the Kingdom of Heaven should be with us." Perhaps it was equally predictable that that prayer would not be fulfilled. Nonetheless, even when the prescriptions laid down at Nuremberg are ignored as cruelly as they have been in Indochina and many other parts of the world in recent years, they cannot be forgotten.

Out of the darkness of World War II, the victors and the survivors developed or created many institutions. Those institutions are designed to rescue us from our own frailty, to bind the self-inflicted wounds of the world. They are man-made, and therefore imperfect. They have high ideals from which they often slip and which, more often, governments prevent them from fulfilling. Criticisms of them in no way suggest that their work is not needed. On the contrary, to deny their importance in a world that is more closely interlinked than ever and, at the same time, also more painfully disparate, would be to deny common humanity.

I was tempted to end my book by saying that despite the viciousness of Cambodia's fate, we have to continue both to hope and to trust in the progress of mankind.

But while hope is essential, it is not enough. And while the very existence and much of the work of the humanitarian organizations testifies to a heartfelt desire for progress, the story of Cambodia -- which is not atypical today -- hardly demonstrates real improvement in international conduct. In the case of Cambodia, the quality of mercy displayed was certainly "twice blessed." But it was also subverted. It gives us little cause for complacency.