NOW LOOK WHAT the United States government is doing in our name -- this time to defenseless refugees.

In the last week of January, along a stretch of no-man's land in southeast Thailand, American immigration officials dispatched 8,000 men , women and children by bus to camps along the Cambodian border. This was the same heavily mined border over which they fled in late 1979 and early 1980 to escape starvation, disease and the Vietnamese communists who have occupied their country with a 200,000-man army ever since.

Now, three years later, the American government has told them they are not refugees.

All have lived through nine years of war. They have survived the dismembering of families, brutish labor, broken hearts, smashed religion and four years of rice soup during Pol Pot's barbarous attempt to remake the Cambodian nation and personality into a mass communist peasantry.

Every form of persuasion -- including a forced repatriation by the Thai government that drove 44,000 Cambodians off the edge of a mountain at gunpoint in 1980 -- has failed to convince these survivors that it is safe to go back to their occupied country.

In the first year of the Reagan administration, the pipeline to resettlement in the United States shut down tight -- just for Cambodians. A consistent pattern of discrimination is evident in the figures. Of 550,000 refugees admitted to America from Southeast Asia since 1975, fewer than 10 percent have been Cambodian. Yet 84,000 of them remain in the last holding center in Thailand, the largest stockpile of human misery waiting for any other alternative to returning to a communist regime, this one dominated by Vietnamese.

Last spring, America appeared to rediscover its humanitarianism when the State Department and Congress agreed to an Olympian "callout" of 21,000 Cambodians. After being identified -- and branded -- of special interest to the United States because of former military service, civilian support to the American-backed Lon Nol government or close family ties in the States, they were called out of the camps they had been in and moved to a special U.S. processing center called Kamput. There they were clothed as trial Americans in Coca Cola T-shirts, stimulated with Voice of America broadcasts and reintroduced to forgotten concepts such as liberty and fairness. The greatest gift of all was to be able to study English. They made blackboards to hang in their concrete block "cages" on which to practice irregular verbs.

Money orders and pictures arrived from eager family members already resettled in the United States. Local churches and families in America waited months with rented apartments or ready homes. Communities like North Conway, N.H., turned themselves inside out to make ready medical facilities for problem cases, even lepers.

Out of the nightmare at last, these 21,000 Cambodians believed they had one foot on the bus to a future in the nation whose bombing of their motherland they were more than happy to forget.

Finally, they were called to their 45-minute audience with a U.S. immigration officer. Some went before "the swearing officer with all the gold," as the refugees call Thomas Prokopowiez, a 250-pound sirloin of a man decorated with gold chains and tattoos.

The Cambodian refugees live in fear of Prokopowiez. "My job is to grate these people," he insisted to an embassy official. "We just can't accept what they're saying." Most of his field officers come from the Border Patrol and are used to operating out of spotter planes over the Rio Grande.

"Why did you come to the border of Thailand?"

"Starving, no food," is usually the Cambodian's first answer.

Rejected. Economic migrant. Not a refugee.

"How many family members did you lose under Pol Pot?"

"All my family."

Rejected. "The loss of family members is not relevant to a well-founded fear of persecution under the government now in power," insists Prokopowiez' boss, Jack Fortner. He wears a large diamond-studded ring.

"Yes, things were very difficult under Pol Pot." he acknowledges. "There wasn't enough food, any medical, they were made to work varying hours." Fortner makes the horrors of the Khmer Rouge era sound like a violation of the terms of a labor agreement. But for his men now, what happened under Pol Pot is irrelevant to the refugees' present status. "When you ask them," Fortner said, " 'What did the Vietnamese do to you?' they say, 'They took my biography.' " The fears they express about returning to Cambodia now Fortner labels "subjective."

He and his field officers operate with such willful capriciousness that their rejection rate veers crazily between different ethnic groups, different officers and their moods on different days of the week. Fortner boasts he has no set guidelines, and there is no appeal from his decision.

Basically, they took a bread knife and hacked this refugee group in half. Thousands of those rejected have parents or children or brothers and sisters who were already accepted; indeed, that was one of the criteria on which they were called out.

"It would be extremely difficult for these people to go back to Cambodia without persecution," says an alarmed official at U.N. headquarters in Bangkok. "And because they have U.S. connections, no other country will ever accept them." With this cruel trick, we have contaminated these people as surely as if we had marked their foreheads with indelible red, white and blue dye.

Fortner and his men enjoy such awesome power because of new U.S. government "processing guidelines" and the attorney general's decree that applicants' stories should be judged on a case-by-case basis.

The Immigreation and Naturalization Service in Washington has cabled instructions to its employes in Bangkok telling them to treat the Cambodians with consideration, to avoid intimidating tactics and when in doubt to employ an "empathy test" -- if what this refugee says, would I want to go back to Cambodia? But Fortner and his bejeweled cowboys give every evidence of ignoring thse instructions. They continue to act as judge, jury and executioners of people who stand before them, amputated of the power to communicate and stripped of the cultural trappings that once assured them dignity.

Yet, on a visit to Thailand last October, William French Smith made what the Thais considered was a committed to taking 64,000 Southeast Asian refugees in fiscal year 1982-83, half of them Cambodians. At the present rate of rejections by INS, only half this commitment could be fulfilled by next fall.

The ugly part is, the immigration cowboys had bragged loudly to the embassy -- a year ago -- that they would reject 90 percent of the Cambodians. So even as the right hand was opening the door, it was clear the left would slam it on at least half of America's commitment.

And when the special ambassador for refugees, Eugene Douglas, came out from Washington to have dinner last December with our ambassador in Bangkok, the true spirit of this administration's refugee policy came to light even more crudely. Ambassador John Gunther Dean, himself a Jewish refugee from Nazi Germany, was making a passionate case for reunifying Cambodian refugees with their family members in America. According to another dinner guest, Douglas muttered that Dean might just turn out to be "Abramowitz II." It was a chilling reference to Dean's predecessor, Morton Abramowitz, whose brilliant Foreign Service career apparently took a nose dive in part because he stuck his neck out for the refugees.

No wonder the Thai government feels betrayed. Their response to our shell game is to force these refugees back from our processing centers to camps in the war zone along the Thai-Cambodian border. On that last bus ride in January, many among America's rejects considered moving into a border camp where civilians lived among the resistance fighters of Prince Sihanouk and former prime minister Son Sann.

Last week, 4,000 Vietnamese troops hammered one of those camps with artillery, mortars and rockets, and burned the camp to the ground. Women, children and noncombatants numbering 53,000 fled into the jungle. Refugee workers report these people fear trying to enter the last refugee camp for Cambodians inside Thailand. The camp is officially closed, and every day shots are fired at those driven by desperation who try to sneak in. The only ones allowed into Khao I Dang camp came back feet first, after the Vietnamese attack into the hospital and morgue.

One more circle around the Dantesque inferno.

Every justification has been provided to declare this group of valiant survivors refugees as a class. The Bangkok embassy's draft report on conditions inside Cambodia reports executions without trial of those believed to be "spies and traitors" because they come from the direction of resistance camps on the border. But the Reagan administration, leading the international community, has apparently decided to handle the human refuse of wars we didn't win in Southeast Asia a little differently. They are to be thrown back to the communist-held border, allotted three feet of space, provided the correct number of calories, given all the right injections, brought up to a healthy weight, so that when they are blown to bits tomorrow by a Vietnamese shell we can say: "Gee, we did all we could."