Two decades after the U.S. government stopped dumping Agent Orange to defoliate the jungles of Vietnam, it is still the bane of veterans who fought there. And the federal government is still refusing to acknowledge that Agent Orange caused an assortment of maladies, including cancer.

There is no compensation for the sufferers and not even a sincere effort on the part of the government to research the link between Agent Orange and disease. In July, a congressional report accused the Reagan administration of ordering researchers at the Centers for Disease Control to juggle the data in an Agent Orange study and say there wasn't enough information for the study.

Recently declassified documents from the Vietnam era now suggest that the government may have had the facts all along.

Memos to and from military and U.S. Embassy officials in Saigon show more than an inkling about the health hazards in the year before the use of Agent Orange was stopped. At the same time, officials had received advice that the defoliation program -- intended primarily to deprive the enemy of cover -- wasn't nearly as effective as it was cracked up to be.

A November 1969 memo to military commanders in Vietnam from the Joint Chiefs of Staff noted that one study by the National Institutes of Health had found that the active ingredients in Agent Orange caused stillbirths and deformities in lab animals.

"Pending decision by the appropriate department on whether this herbicide can remain on the domestic market, defoliation missions in South Vietnam using Orange should be targeted only for areas remote from population," the memo said. Yet the Pentagon continued to use Agent Orange, letting it rain down not only on Vietnamese peasants and their crops, but on American troops too.

A Pentagon spokesman, responding to questions about that memo and others, told our associate Dan Njegomir that the Defense Department "absolutely didn't know what the effects were going to be at the time."

Yet the once-secret documents suggest the military was at least nervous about Agent Orange's potential. One document, explaining how to clean spent canisters of the defoliant, is almost comical. The instructions promise that there is little safety hazard "if proper directions are followed." But the "proper directions" are so elaborate they imply the chemical is as stubborn and virulent as poison ivy.

While the military stubbornly clung to Agent Orange, at least one of the Army's own studies said its use as a military tactic was dubious. A 1968 summary of Agent Orange said that it had "little lasting effect" when used to destroy the crops that peasants were growing for the Viet Cong. The peasants would replant as soon as their crops were destroyed.

In the long run, the Army was wrong if it concluded that Agent Orange had no effect. Just ask the Vietnam vets who had it dropped on them. They survived the war, but some may yet pay the ultimate price.