A setback in Lebanon did not do irrep-arable damage to the Soviet standing in the Arab world. Soviet advances in Egypt are particularly disturbing. Moscow and Cairo have already reached an agreement to upgrade their diplomatic ties to the full ambassadorial level. Soviet-Egyptian trade is growing. And a limited number of Soviet nonmilitary advisers have been admitted back to Egypt. Senior officials in Cairo openly indicate their interest in friendly relations with the USSR.
There is no reason for Washington to be concerned, Egyptian spokesmen argue. President Hosni Mubarak's government is committed to preserving a special relationship with the United States. This relationship is based on commonality of strategic objectives, on an appreciation that only America can solve the Arab-Israeli dispute, and also, of course, on billions of dollars of US economic and military aid.
Even a collapse of Ronald Reagan's peace initiative is not expected to cause serious trouble in the partnership. Boutrus Ghali, Egyptian minister of state for foreign affairs, told me during a conversation in his office that the Egyptians from the beginning were not terribly optimistic about prospects of the Reagan administration offering the PLO enough incentive to approve King Hussein's joining negotiations on the Palestinian issue. So they are preparing fallback approaches which will allow Egypt to live through a forthcoming US presidential campaign - a period rarely conducive to an effective US diplomacy in the Mideast. According to official sources in Cairo, in order to avoid unnecessary friction between friends, all these approaches will be carefully coordinated with Washington.
Yet, outside the halls of government, America is increasingly becoming the target of a sharp and, on occasion, vicious attack. At a recent seminar in Cairo jointly sponsored by the Georgetown University Center for Contemporary Arab Studies and the Al-Ahram Center for Strategic and Political Studies, an influential Egyptian scholar with strong ties to the official establishment charged that the US bears full responsibility for Israeli conduct. No compromise with Israel is possible, he said. And the Soviet Union will make a major contribution in helping them to develop a military option against the Jewish state.
''Don't take our eggheads too seriously,'' a senior Egyptian official cautioned me. But he admitted that the frustration is growing and it is directed both against America and by association against the Mubarak government. The govern-ment's response to the effect that there is no realistic alternative to a continuing reliance on Washington falls on the deaf ears of a more and more vocal and assertive political opposition.
Radical, nationalist chic which flourished during the '60s is in fashion again. The most ridiculous romantic schemes of punishing the ''Zionist enemy'' and its American patrons are acquiring political currency. And the Soviet Union - its previous faults forgiven if not forgotten - is expected to play a role in implementing them. At a minimum, a growing body of Arab opinion is moving toward bringing the Kremlin back into the peace process.
Moscow is understandably intrigued. The Soviet media coverage of Egypt has changed considerably since Sadat's days. The Kremlin's commentators still hesitate to predict that rapprochement with Egypt is imminent. But despite their customary caution, Soviet journalists claim that ''changes for the better'' are in the air.
In other Arab countries the Soviets are gaining ground as well. After months of tension, their standing in Iraq is again on the rise. Syria, whose trust in Soviet reliability as a superpower patron was shaken by the war in Lebanon, is impressed with Moscow's willingness to deploy SAM-5 missiles and to staff them with Red Army personnel. The PLO, cold-shouldered by the US, is as ever dependent on the Kremlin's support. Libya is planning to sign a friendship and cooperation treaty with Russia.
Even traditionally pro-Western Jordan, frustrated with a US unwillingness to supply Hawk mobile antiaircraft missiles and to constrain Israel's assertiveness , turned for arms to the USSR. The Kremlin was only too willing to oblige. It provided King Hussein with two air defense systems - SAM-8 missiles and ZSU-23/4 self-pro-pelled guns. Soviet military technicians have quietly arrived to install the weapons and to train the Jordanians.
Every additional week of Israeli presence in Lebanon does damage to US credibility. Every new Israeli settlement helps Moscow to score propaganda points with the Arabs. In a spare moment, when he is not busy denouncing the Soviet ''evil empire,'' Mr. Rea-gan might address the question of how long Begin will be allowed to act as a magnet for Soviet penetration of the Middle East.
An erosion of the Reagan initiative based on the Camp David accords cannot but please the Politburo. Yuri Andropov demonstrates every determination to prove Soviet relevance in the Mideast. His credibility in the region is still uncertain. But so is that of the US.