WHEN the United States went to war in Vietnam, policymakers and the public alike knew almost nothing of Vietnamese history, politics, culture or values. We fought, failed and left in the same state -- "still ignorant," as the scholar John K. Fairbank observed, "even of the depth of our ignorance."

Ten years after the war it is difficult to say whether we are more ignorant, or less. Time has blurred some of the painful realities and allowed them to be replaced by myths, such as the belief that U.S. policies could have succeeded if we had only stuck to them a little longer. But there is also a growing impulse, evidenced by a lengthening shelf of books and the increasing popularity of Vietnam courses at colleges and universities, to reexamine the war and the disastrous failure of the American effort.

For those who share that impulse, here are some reading suggestions -- not a comprehensive list, but a guide to a selection of 10.2,8>worthwhile books, some well known and some forgotten, on various aspects of the war. Historical Perspectives

FOR A SINGLE, panoramic view of the war and its setting, the best book is unquestionably Stanley Karnow's Vietnam: A History (Viking, 1983; Penguin paperback).

Published in conjunction with (but much more informative than) public television's 1983 series on the war, this careful, factual account covers the entire sweep of events from the 1945 anti-French uprising to the communist victory three decades later. It also provides useful chapters on Vietnam's earlier history and nationalist tradition, along with a memorable look at postwar Vietnam under its "liberators" -- a drab, sad place, Karnow found, of poverty, fading hopes, and tattered myths of revolutionary heroism.

Avoiding the common but misleading American-centered view of the war, Vietnam: A History shows plainly that the conflict arose from and was ultimately decided by the forces of Vietnamese history, not by U.S. policy choices.

An even greater merit is its freedom from both the anti-communist and anti-war mythologies. Karnow makes clear that cruelty and callous strategies existed on all sides -- as does the guilt for an immense burden of suffering, death and desolation.

Also essential for understanding the war's setting are the works of Bernard Fall, particularly his classic The Two Vietnams, originally published by Praeger in 1963. (Revised editions followed in 1964 and 1967.) More than 20 years after it first appeared, this book by the French-born Fall -- who was killed in action early in 1967 -- remains indispensable for its lucid historical background and its authoritative portraits of the Saigon and Hanoi regimes at the time of the fateful U.S. decision to enter the war. Americans at War

AMONG the many combat narratives of Vietnam, one that will endure is Philip Caputo's A Rumor of War (Holt, Rinehart and Winston, 1977; currently available in Ballantine paperback).

Caputo, who was a young Marine lieutenant in the very first U.S. combat unit deployed to Vietnam, is a writer of intense passion with an extraordinary gift for portraying the sights and sensations of combat. This memoir is filled with the special ambiguities and frustrations of Vietnam but also powerfully conveys the universals of the experience -- "the things men do in war," as Caputo's prologue put it, "and the things war does to them."

A very different story of Vietnam combat is The Village, by F.J. West, Jr. (Harper & Row, 1972). This is an absorbing account of a 12-man Marine unit that fought alongside South Vietnamese militamen for many months trying to drive the Viet Cong out of a single village called Binh Nghia in Quang Ngai province, not very far from another Quang Ngai village called My Lai.

Unlike most U.S. troops, who fought an American war of firepower and advanced technology, the Marines of West's story -- and a handful of others in similar combined- action detachments -- knew the war as the rural Vietnamese knew it: a war with a strange kind of violent intimacy, fought by small groups of men, mostly at night, with rifles and shotguns and grenades and crude boobytraps in the space of a few square miles of rice paddies, marshes and sand dunes. West, who served as a Marine officer in Vietnam, tells the story vividly and well.

Equally vivid is Ronald Glasser's 365 Days (Braziller, 1971). The author, an Army doctor in Japan, collected his patients' stories and set them down, thinly fictionalized, in this book. The sketches come together to form a searing, unforgettable impression of young Americans in a war that was both terrifying and mystifying to those who fought it.

Vietnamese Viewpoints

OF ALL perspectives on the war, the one that remains least accessible to American readers, oddly, is not our enemy's but that of our South Vietnamese allies. One of the very few books reflecting that viewpoint and experience is The Will of Heaven, by Nguyen Ngoc Ngan (with E.E. Richey; Dutton, 1982). Ngan saw several years of combat as a young infantry officer in the South Vietnamese army, and then spent years in communist "reeducation" camps. He finally escaped in the exodus of the Boat People, but his wife and young son drowned in the attempt. His striking account of those experiences is a moving capsule of South Vietnam's long tragedy.

Also reflecting the South Vietnamese perspective is a series of studies called the Indochina Monographs, written for the U.S. Army Center of Military History by a number of former high-ranking Saigon officers who reached the United States after the war. These were not published for public sale, but can be found in the overnment documents sections of most large public or university libraries.

Views of the war from the communist side can be found in Our Great Spring Victory, by Gen. Van Tien Dung, who was the field commander of the final North Vietnames offensive (Monthly Review Press, 1977), and A Vietcong Memoir, by Truong Nhu Tang, being published this month by Harcourt Brace Jovanovich (see page 1 of Book World for a review). Tang, a founding member of the National Liberation Front, writes fascinatingly of the development and strategies of the southern guerrilla movement; he also describes the growing tensions between the southern revolutionaries and the Hanoi leadership, which eventually led to his own disillusionment and escape into exile. His memoir will give no comfort to those who designed or carried out U.S. policies, which appear in these pages as clumsy, politically blind and ineffective.

Among books by Western authors on Vietnamese communism, two useful and readable studies are Jean Lacouture's Ho Chi Minh (Random House, 1968) and Robert F. Turner's Vietnamese Communism: Its Origins and Development (Hoover Institution, 1975. U.S. Policies

IN THE U.S. WAR, the 1968 Tet Offensive was the pivotal event. Don Oberdorfer's Tet! (Doubleday, 1971; reissued by Da Capo Books, 1984) reconstructs both the battles in Vietnam and the political upheaval in Washington. Oberdorfer, one of the best and wisest of all American reporters, showed in this book what journalism at its best can be: careful, fair, thorough and thoughtful. The extent of his achievement is shown by the fact that 17 years after Tet, his account has still not been seriously challenged.

Gen. William C. Westmoreland's A Soldier Reports (Doubleday, 1976) expresses the conventional military theology that American military policy was sound, and success was prevented only by unwise or timorous politicians.

Unlike most other memoirs by senior Vietnam-era commanders, however, Westmoreland's is not primarily a polemic. It is a factual, straightforward and lucid record of what the U.S. command did, and why. Despite moments of political or cultural blindness ("Vietnamese have greater tolerance for cruelty than most Americans"; "some South Vietnamese leaders were stubbornly certain that their own way was better"), this is essential for an understanding of how the American Army fought the war.

The Counterinsurgency Era, by former CIA official Douglas Blaufarb (Free Press, 1977) didn't get much attention when it was published; nor has it been rediscovered, so far, in the current Vietnam revival. It deserves to be. Blaufarb understood what very few American officials ever learned: that the strengths and weaknesses of the two Vietnamese sides were the decisive factors in the war, and that the United States, for all its power, had almost no ability to change those qualities.

For American policy during the clsing years of the conflict, the essential material is in Henry Kissinger's White House Years and Years of Upheaval (Little, Brown, 1979 and 1982 respectively). Kissinger's account is selective and self-serving, written with more concern for his own reputation than for historical truth. But the careful reader who filters out his misleading interpretations and distorted logic will find an enormous amount of information that is available from no other source. The Sideshow Wars

THERE WAS a special sadness about Cambodia and Laos, victims of geography and the mistakes, ambitions and cynical strategies of more powerful nations.

Cambodia's tragedy has been best told by the British author William Shawcross. His 1979 book Sideshow (Simon and Schuster) chronicled the 1970-75 war between the communists and the U.S.-backed Lon Nol regime. Though unsparingly critical of the Vietnamese as well, Shawcross portrayed American policy as both heartless and futile.

Shawcross made some factual errors, which Kissinger and other former Nixon aides have used to try to discredit his book. But by any fair measure, it remains a devastating indictment of Washington's role in a terrible and needless catastrophe.

His second book, The Quality of Mercy (Simon and Schuster, 1984) examined the Khmer Rouge holocaust, the Cambodian-Vietnamese conflict, the refugee crisis, and the international response to those events. Our civilization's conscience is the real subject of this complex, disturbing book.

The atrocities of the Khmer Rouge are documented in Murder of a Gentle Land, by John Barron and Anthony Paul (Readers Digest Press, 1977), and Cambodia Year Zero, by a French priest, Francois Ponchaud, who saw the beginning of the Khmer Rouge period (Holt, Rinehart & Winston, 1978).

Laos, all but unnoticed by Americans during the war, remains so. The best study is still Conflict in Laos, by Arthur J. Dommen (Praeger, revised edition, 1971). The Aftermath

MYRA MACPHERSON tried to do much too much in Long Time Passing: Vietnam and the Haunted Generation (Doubleday, 1984). Not even a book of this bulk (672 pages) could adequately treat all the issues, from amnesty to Agent Orange to atrocities to post-traumatic stress. But her interviews -- with veterans, war protesters, and those who spent the war as MacPherson herself did, in numb confusion -- provide vivid evidence of how profoundly all Americans were affected and changed by the war, and how far we still are from coming to terms with it.

Two other books illuminating the postwar debates are On Strategy by Col. Harry G. Summers Jr. (Presidio, 1982) and Vietnam Reconsidered, edited by Harrison E. Salisbury (Harper & Row, 1984).

Summers' provocative critique of the U.S. military effort has become quite influential among military theorists -- though his book may be best remembered for an exchange between the author and a North Vietnamese liaison officer just before Saigon fell. "You know you never defeated us on the battlefield," Summers said in some anguish, to which the communist officer replied: "That may be so, but it is also irrelevant."

Vietnam Reconsidered, drawn from the proceedings of a 1983 conference at the University of Southern California, presents some of the lingering arguments in lively fashion. Of particular interest are the comments of numerous journalists and their critics on the coverage of the war -- a subject, as these exchanges make clear, of continuing controversy. Documents

THE BEST-KNOWN trove of Vietnam war documents is the secret Defense Department history known as the Pentagon Papers.

The most useful version is the five-volume set published by Beacon Press, usually called the Mike Gravel edition after its editor, the former U.S. senator from Alaska. A much more limited set of extracts was published in book form by The New York Times (Bantam, 1971). The complete version, as released by the Pentagon to Congress, can be found in libraries, but its almost unintelligible structure makes it maddeningly difficult to use.

A useful collection is Vietnam: The Definitive Documentation of Human Decisions (Earl Coleman Enterprises, 1979), edited by Gareth Porter. And many significant texts are in various editions of a Senate Foreign Relations Committee publication, Background Information Relating to Southeast Asia and Vietnam. The seventh and last revised edition was published by the Government Printing Office in 1974; it is now out of print, alas, but is available in libraries. A Wider View

ANYONE SEEKING to understand Vietnam and the American failure there should perhaps also read these two last selections, even though one devotes only 15 pages or so to Vietnam -- and the other never mentions it at all.

Sentimental Imperialists, by James C. Thomson Jr., Peter W. Stanley, and John Curtis Perry (Harper & Row, 1981), gives Vietnam its context by telling the much longer story of a turbulent and troubled American relationship with Asia. And Barbara Tuchman's Stilwell and the American Experience in China (Macmillan, 1970) shows that the miscalculations and blindnesses of our Vietnam disaster were not new. All were presaged, a generation before, in our failed effort to ward off revolution in China by supporting a moribund Nationalist government. China was a problem for which there was no American solution, Tuchman wrote; her book ends with this sentence: "In the end China went her own way as if the Americans had never come." The epitaph for our long, painful and doomed effort in Vietnam could be the same.

Arnold R. Isaacs, a former editor and reporter for The Baltimore Sun, is the author of "Without Honor: Defeat in Vietnam and Cambodia."