ON THE AFTERNOON of Friday, Sept. 29, military attaches representing the army, navy and air force of Argentina were called to the Pentagon and given a piece of bad news. Because of the Argentine government's dismal human rights record, the State Department had decided to turn down 212 pending license requests for the sale of nearly $100 million worth of U.S. military equipment to Argentina's armed forces.

The massive turndown came one day before the Oct. 1 deadline for the complete cutoff of all such sales to Argentina's ruling military junta. Originally scheduled to take effect one year earlier, in 1977, the cutoff had been postponed when the administration persuaded its sponsor, Sen. Edward M. Kennedy (D-Mass.), to amend the deadline to give the State Department a year of "maneuvering room" to try a carrot-and-stick approach in persuading the junta to change its repressive ways.

Few such changes had been forthcoming over the year. More than 15,000 Argentines, according to Amnesty International, are still among the missing, with many presumed dead, after allegedly being kidnapped or arrested by government security forces. "We see nothing," Assistant Secretary of State for Human Rights Patricia Derian said in congressional testimony last August, "to indicate there is a genuine trend toward human rights in Argentina."

Accordingly, what one State Department official involved in the decision called the "vast majority" of munitions license requests still pending as the deadline approached were turned down. The denials, the official said, "send an unmistakable message to the Argentines" of U.S. disapproval. A Series of Exceptions

BUT DID THEY?In the months preceding the deadline, when Derian had seen "nothing" to indicate human rights improvement, the State Department had authorized nearly $120 million in military sales to the junta, including five Chinook helicopters, two C130 military transports and 15 Beechcraft trainer aircraft.

In fact, on the same day the State Department was "messaging" the Argentines with the 212 denials, it approved more than 30 training slots for Argentine officers at U.S. military installations.

Even the department itself did not seem sure if its message was one of encouraging carrots or punishing sticks. While Washington officials touted the denials as evidence the administration was fed up with the junta, U.S. Ambassador to Argentina Raul Castro, in a recent interview in Buenos Aires, didn't even mention them.

Instead, Castro announced that the Carter administration had decided to suspend its policy of imposing largely ineffective and often counterproductive sanctions against the junta in favor of incentives to encourage human rights improvements. As evidence of the new incentives policy, Castro pointed to several "overt acts," including the training, the helicopters and what another embassy official called lots of "other stuff" sold to Argentina.

Regardless of the interpretation the junta puts on this somewhat confusing set of circumstances, the fact is that the sale of major defense items to Argentina over the past year has had little to do with human rights. In many cases, the sales have been "exceptions" to legislative restrictions, licensed by virtue of State Department discretionary authority, because of pressure by a U.S. company or its representative in Congress.

The government's human rights watchdogs have consistently condemned the junta, and repeatedly deemed it ineligible for such sales, as well as for U.S. government-guaranteed and multilateral loans. But those concerned with problems closer to home, such as domestic employment, the balance of payments, profits and military security - including the Commerce and Treasury departments - the Pentagon and private industry - have argued, in many cases successfully, that human rights sanctions are costing an exorbitant price in U.S. jobs, trade and overseas allies. Practice and Principle

THE CONFLICT between U.S. moral, economic and security priorities is not a new one. But beginning perhaps with the 1971 passage and subsequent repeal of the Byrd Amendment exempting vital chrome imports from United Nations trade sanctions against Rhodesia's white minority government, it has grown to the point of outright war under the human rights-conscious Carter administration. With a focus on rights violations in Argentina - and what the United States can and should do about them - the battle between domestic and foreign policy interests is threatening the entire foundation of the administration's human rights campaign.

While the conflict certainly did not begin with Carter, and he was not the first candidate or president to set human rights as a policy priority, by the time he had been in office barely a month it seemed he had invented the concept.

He spoke about it at every opportunity, repeatedly defining the concept and his concern about it. On various occasions, Carter has defined human rights as "free speech . . . respect for the individuality of persons . . . the chance to express one's political beliefs . . . freedom to speak and think as one pleases . . . to participate in the determinination of [one's] destiny . . . freedom from torture . . . from prolonged imprisonment without charge."

Those concepts, Carter has said, are "an expression of the most deeply felt values of the American people." His stand on them "is compatible with the consciousness of this country" and "almost overwhelmingly supported by the American people."

The immediate question was what to do about human rights violators. On March 16, 1977, Carter told a town meeting in Clinton, Mass., that the United States "ought to have a right to express displeasure and to do something about" violations. Two days later, he said the administration was "reforming the policies which have, on occasion, awarded liberal grants and loans to repressive regimes."

Later, Carter noted that he had "reduced military relationships which in some countries in the past have seemed to support repressive regimes . . . Our foreign assistance programs will now reflect more clearly our concern about human rights."

The problem quickly became which countries would be the recipients of "expressed displeasure" and which would suffer "reformed policies." Clearly, the Soviet Union, to which the United States neither sold arms nor give aid, could not be deprived of such assistance. At the same time, national security interests prevented Carter from doing much more than expressing severe displeasure, as in the case of dissident Anatoly Scharansky, often and loudly in the early months of his administration.

Repressive but friendly governments in strategically important countries like Iran and South Korea were similarly exempted from reformed U.S. policy. What was left was a group of Third World, primarily Latin American countries which met the triple criteria of having repressive governments, little economic or strategic importance, and either an embarrasing previous connection with the United States or evidence of Soviet support.

Thus, in early March last year, Carter announced cuts in military assistance to Argentina, Uruguay and Ethiopa. Although a number of other Latin American countries, including Brazil and El Salvador, angrily cancelled their own bilateral military aid agreements with the United States, none of the cutbacks provoked much domestic outcry.

As the human rights situation in Argentina grew worse, however, Congress began legislating more severe sanctions, first prohibiting all military assistance, and finally, with the Kennedy proposal, cancelling even private sales to the junta by U.S. defense contractors. That action had previously had previously been applied only to Chile, whose military regime was so notorious that the bad publicity to be gained by trading with it outweighed economic gains for most U.S. exporters. The Junta's PR Campaign

THE FACT that economic interests in the United States chose to challenge the human rights sanctions over the case of Argentina is due not only to the severity of the sanctions, but also to the U.S. unemployment rate, last year's $31 billion balance of trade deficit and, perhaps most importantly, to a multimillion-dollar junta public relations and lobbying campaign that both attempted to justify repression showed U.S. exporters what they were missing.

The campaign was spelled out in a proposal to the junta by Burson-Marsteller, a New York public relations agency it now employs. Rather than implementing and publicizing human rights improvements, the agency proposed in a mid-1977 memo. Argentina should "project a new, progressive and stable image throughout the world."

The campaign was targeted at three main audiences: "those who influence thinking, which includes the press, government functionaries and educators . . . those who influence investments . . . and those who influence travel, which includes travel agents, travel writers, airline personnel and tour operators."

In addition to government-organized tours for journalists, businessmen and members of Congress, the campaign included pages of advertising in a number of U.S. magazines and newspapers, most running along the lines of a four-page New York Times supplement last June that told "the whole truth" about Argentina, the leftist terrorism that had provoked repression and the Marxist propaganda about the junta spread abroad.

A 17-page supplement in Nation's Business called Argentina "the best location in today's world for private investments, production facilities and United States exports." Economy Minister Jose Martinez de Hoz made several trips to the United States in which he spoke primarily to bankers and businessmen and, according to a lengthy article in the Buenos Aires magazine Siete Dias, "broke the trap" of sanctions by assuring investors of "the degree of institutional stability" in Argentina.

Armed with evidence that the Argentine violations case had been overstated, and assurances of sales, U.S. business began to take issue with the human rights sanctions policy.

At the same time, the State Department carrot-and-stick policy, in the absence of substantial junta rights improvements, began to appear confused, and there followed a series of seemingly contradictory decisions. Protests and Pressure

IN LATE OCTOBER 1977, House Speaker Thomas P. O'Neill and Rep. Silvio Conte, both of Massachusetts, protested in a letter to Secretary of State Cyrus Vance that his human rights bureau was unnecessarily delaying license approval for an order of periscopes, made by Kollmorgen Co., of Northampton, Mass., for Argentina's German-built submarine fleet. Apparently the threat of lost Massachusetts jobs and income, combined with the fact that most Kollmorgen periscopes are sold to the U.S. Navy, whose costs go down the more are sold abroad, brought results. On Nov. 3, despite the fact that the periscopes were among controlled munitions items, not to be released unless rights improvements could be shown, the approval came through.

Perhaps the most propitious time for license approvals over the past year has been whenever a high-level U.S. mission has traveled to Argentina hoping for what one State Department official called "a big breakthrough" in human rights improvements in response to U.S. prodding. Just prior to those trips, the State Department normally tries, the official said, "to create a climate" for Argentine concessions.

An application for the sale of Boeing-Vertol helicopters to the junta arrived at the State Department just before Vance's trip to Argentina last November. Accordingly, Boeing was given an "advisory" opinion stating that the license was likely to be approved and signed a contract. Although Vance came home with virtually no Argentine rights concessions, and State cautioned that the "advisory" in no way guaranteed license approval, the sale of five helicopters was eventually approved.

"You have no idea of the pressure" Boeing exerted, said another State Department source. Without the Argentine order, the company warned it would have to close an assembly line and lay off workers. At the same time, the junta pointedly told Boeing it might buy its helicopters elsewhere and might place all future orders with a European competitor.

A department spokesman defended the helicopter approval by saying that three of the five requested were outfitted for operation in Argentina's Antarctic naval bases, where it was felt they would not be involved in repressive military operations.

Other licenses, the official said, were for even more innocuous items. In one case, Argentina and the seller of a previously purchased C130 troop transport requested and received a license to fly it back to the United States for a new paint job.

"The Argentines were going to sue" the seller for the initial faulty painting, the official said, "so we let him bring it back in."

"We get into the ridicule factor here," the official said. "It's hard to tell a guy that our human rights policy doesn't permit us to allow him" to paint an airplane. "Playing Politics With U.S. Exports"

THE DEPARTMENT came in for more than ridicule, however, with last summer's denial of a $270 million Export-Import Bank loan for the Argentine purchase of turbine generators from Allis-Chalmers Corp. "From an economic and financial point of view," bank chairman John Moore said, "the proposed transaction is clearly the kind of project in Argentina which we would be prepared to consider favorably for financial assistance."

Yet Moore noted that, under law, he was forced to "take into account the observance and respect for human rights in countries receiving exports we support with loans or financial guarantees."

The denial, one of the biggest nonmilitary projects ever turned down on human rights grounds, was the catalyst for cries of outrage against Derian's office.

In testimony July 19 before the House Inter-American Affairs subcommittee, defense industry spokesman Joseph E. Karth protested that sanctions against Argentina had cost an estimated "$813.5 million . . . lost jobs to American workers . . . loss of American influence on the behavior of other nations."

"The administration and Congress often cannot resist the attempt to impose our moral and political values on someone else, and the weapon closest at hand is often economic sanctions," Karth said. "But playing politics with U.S. exports, playing politics with the American economy, has become increasingly risky."

Commerce Secretary Juanita Kreps opposed the use of U.S. trade as a "political gesture" in a pointed reference to rights sanctions and another high-level Commerce official accused the administration of "tilting the balance" toward human rights sanctions and away from balance of payments problems.

Beech Aircraft, with a $10 million Argentine order worth 10 per cent of its total 1978 export volume on the line, protested that "human rights policies are administered without a balanced approach . . . sometimes according to the personal prejudices of State Department officials" who make the policy decisions. Besides, Beech echoed the Argentine advertisements, "in Argentina, human rights violations are reactions by the [junta] to attempts at violent overthrow by terrorists . . . The Argentine government is gradually restoring stability."

During the last week in September, at the same time the 212 munitions licenses were turned down, the State Department reversed its denial of the Allis-Chalmers Exports-Import Bank loan. While no one pointed to human rights improvements as a reason for the reversal, a State Department spokesman said the administration had "expectations" of improvement.

The expectations were based on a private promise made to the U.S. government by Argentine President Jorge Rafael Videla in August that the junta would allow an inspection of its prisons by the Organization of American States Human Rights Commission. The same promise, informed sources said, had been made without results to Vance last November, and to Undersecretary of State David Newsom in a visit to Argentina last spring.

Last week, the junta publicly invited such OAS inspection. While the State Department has called the invitation a clear indication that the carrots worked, sources in the Bureau of Human Rights say it was the sticks. "It's more a case of economics than human rights," one source said. With continued high inflation and restricted imports, the junta "has not been able to meet the needs of the middle class. It has nothing to do with human rights; it's a problem of not being creditworthy."

In other words, what may eventually end human rights violations in Argentina is the same thing that may eventually end the administration's human rights policy. It's just too expensive.