President Carter, in deciding to involve the Soviet Union in a declaration of objectives for an Arab-Israeli settlement, has perhaps taken an inevitable step along the thorny diplomatic path to peace in the Middle East.

While the President seems to be going in a different direction from that followed since the early Nixon administration, the Soviet Union has always been seen as an immovable object on the Middle East landscape - one that would have to be reckoned with at some point.

The question that Carter's latest action raises is whether this is the right time for the reckoning.

During the Nixon and Ford administrations Secretary of State Henry A. Kissinger strove persistently to reduce Soviet influence in the region and at one point spoke of expelling the Russians from Egypt.

But by mid-1975 Kissinger's diplomatic tactics in the Middle East were coming under criticism. His step-by-step and widely publicized shuttle diplomacy showed little prospect of producing positive results. The presidential campaign was impending and foreign policy experts who aspired to high office in a new Democratic administration were busy devising alternative approaches to the Middle East quarmire.

One academician - Zbigniew Brzezinski - wrote an article that summer advocating a "territorial arrangement" guaranteed by the United States and the Soviet Union and envisioning the creation of a Palestinian state.

Brzezinski, who is now Carter's national security affairs adviser, went to Israel in June, 1976, with the encouragement of some of Carter's Jewish backers in the presidential campaign. Brzezinski said privately afterward he was afraid Jews might block his entry into the Carter administration.

In statements after his trip Brzezinski "sounded more pro-Israel than the Israelis," according to one Middle East expect. He backed away from the idea of a Palestinian state, which, he had written in the journal, Foreign Policy, might even exist alongside Israel in a spirit of economic cooperation.

But he had not given up his strong feeling that a comprehensive settlement of Arab-Israeli problems should be attempted by reconvening the Geneva conference that had fizzled after only two days of meetings in December, 1973, and that the Soviets should be engaged in such an effort.

Carter himself had favored a similar approach during the campaign. In an interview that appeared in the Chicago Tribune May 8, 1976, Carter said:

"It may be that some time in the future, after unpublicized negotiations between us and the Soviet Union, we might jointly make a public proposal of a sol lution to the Middle East . . . The Soviet Union is going to have to participate in a forceful way before Syria will be amenable to any productive negotiations with Israel."

Carter also said in the same interview that "ultimately the legitimate interests of the Palestinians are going to have to be recognized. I would not negotiate with the PLO [Palestine Liberation Organization], nor would I try to force Israel to do that, until I was convinced that the Palestinians do recognize Israel's right to exist in peace in the Middle East. after that, negotiations could proceed to meet the needs of the Palestinians."

The U.S. Soviet joint declaration issued in New York on Oct. 1 recognized "the legitimate rights of the Palestine people" but did not mention the PLO, which claims to be the legistimate representative of the 3 million Palestinians. It also called for establishment of "normal peaceful relations" in the region - long an Israeli goal.

In 1970 the Soviets moved into the Middle East in a major way by providing pilots and planes to Egypt in its air defense against Israel.

Kissinger, who was then Richard M. Nixon's national security affairs adviser, said during a background briefing for reporters at the San Clemente White House that there was an ultimate need to "expel" the Soviet air capacity from Egypt.

No action was taken, but later that year, when Soviet-backed Syrian troops invaded Jordan, the United States rattled sabers all over Europe and the Middle East, putting troops on alert and warning of a possible Israeli reaction. The Soviets and Syrians backed off.

Then in 1972 Egyptian President Anwar Sadat, angered by the failure of the Soviets to supply as many weapons as he wanted, expelled the Russians.

After that, their direct interest in the region has been mainly as an arms supplier to Syria and Iraq and as a prime backer of the PLO.

After the October, 1973, Arab-Israeli war, Kissinger went to Moscow and persuaded the Soviets to co-sponsor a Geneva conference. When that failed, he began his shuttle diplomacy to secure a disengagement in small steps.

"He generally kept the Russian informed," said one high official in the Nixon-Ford administrations. "But the Russians were constantly complaining that we weren't cutting thing them in. However, they kept talking of a comprehensive solution and that turned off the Arabs. In effect, they were dealing themselves out."

Kissinger's shuttle diplomacy succeeded in getting the Israelis and Egyptians to disengage in the Sinai in January, 1974, and in working out an Israeli withdrawal from part of the Syrian Golan Heights in May, 1974.

But when he failed to secure a second Sinal disengagement in March, 1975, he began a seriousd reappraisal of the piece-by-piece approach.

That May he met with members of Congress, Jewish leaders, such foreign policy establishment figures as former Under Secretary of State George W. Ball, and academics, including Brzezinski, then a Columbia University professor.

Ball advocated Soviet-American co-operation in fashioning a comprehensive agreement and a return to Geneva. According to Edward R. R. Sheehan's book, "The Arabs, Israelis, and Kissinger," President Ford and Kissinger seriously considered the option but were afraid of its political repercussions.

Then on May 21, 1975, the option was in effect killed by a letter from 76 senators urging Ford to endorse Israeli's plea for "defensible borders" and to send massive economic and military aid to the beleaguered country. Sheehan called the letter "a capital rebuke for Kissinger" and "Israel's riposte to reassessment."

So Kissinger went back to step-by-step diplomacy, and in September succeeded in arranging a second Israeli-Egyptian disengagement. That was the last hurrah for shuttle diplomacy.

Kissinger said in a speech on Sept. 16, 1975, that the United States was prepared to work with the Soviet Union and that he expected "ultimately" that the step-by-step process "wold bring about the conditons for an overall settlement."

Yet he never publicly spelled out when that settlement could come and is said to feel privately that now may not be the time.

In December, 1975, the Brookings Institution, an economic and foreign policy research organized here, published a report that incorporated the views of both the pro-Israel and pro-Arab factions among its 16 members.

Because Brzezinski and one of his aides, William Quandt, were members, the report is considered to have had considerable influence on Carter. It said of the Soviet Union:

"It is not yet clear how far it is prepared to work for a general settlement, but since its cooperation would certainly be helpful and may prove essential, its participation in preparing and conducting negotiations should be actively sought and its intentions thus thoroughly tested."

While Israel, the U.S. Jewish community, and Republican leaders have complained about the new Soviet position, predicting that it will only create mischief for Israel, the State Department has sought to minimize the Russian role.

"There's less than meets the eye," said one department source. "Where are the Soviets now? They are actively dealing only with Syria and the PLO, and we're the only ones talking to everybody. We're still the only broker."