Jerusalem — In the short run, Israel undoubtedly is the main beneficiary of Arab disunity -- as dramatized most vividly in the massive military facedown along the Syrian-Jordanian border
But ultimately, Arab disunity is likely to frustrate two of the Jewish state's most critical needs;
* A modus vivendi with the Palestians.
* A comprehensive peace with the rest of the Arab world.
Even the immediate strategical considerations inherent in the prospective Syrian assault on Jordan pose a dilemma for Israel's leaders.
One school of thought would urge concrete military moves to help Jordan's King Hussein hold of a Syrian onslaught.
Another would let the Jordanian monarch fend for himself -- even if the result were his replacement by a republican government dominated by Palestine, who already constitute the numerical majority in Jordan.
The later attitude is favored by some of Israel's most outspoken hawks, especially Agriculture Minister Ariel Sharon, long an advocate of King Hussein's overthrow and the establishment of a Palestian state east of the Jordan River. Mr. Sharon presumably thinks this would satisfy Palestinian political requirements and let Israel do as it pleases with areas of the river's West Bank under its military occupation.
One of Israel's most prominent doves, editor-parliamentarian Uri Avnery, subscribes to the view that inter-Arab disputes are anethema to the peacemaking process.
The very existence of ideological and political conflict tends to make Arab statesmen vie with one another in their expression of hostility against the perennial common enemy, Israel, according to this analysis.
In fact, Egypt's President Anwar Sadat launched his unprecedented peace initiative three years ago in the mistaken belief that it would not only win the support of moderate Arab states situated on the periphery of the confrontation with Israel, such as Morocco, Tuniska, Sudan, and Kuwait (if not Saudi Arabia, too), but also Jordan and even Syria.
So confident was he in the magnetism of the peace process that the Egyptian leader was undeterred by Syrian President Hafez Assad's stern rebuff on the eye of Mr. Sadat's historic flight to Ben-Gurion airport, Nov. 19, 1977. He expected King Hussein to follow Egypt's lead and Syria's President Assad to have no choice except to enter later.
One of the reasons for concern over the Israeli's-Egyptian peace treaty's durability is precisely the diplomatic isolation it imposed on the Sadat government.
By extension, one of Mr. Assad's secondary motives in staging his current armored threat against Jordan is to prevent King Hussein from showing interest in the "Jordanian option" as a potential alternative to autonomy for the West Bank. Syria does not want to see Jordan acting as a substitute for the Palestine Liberation Organizations (PLO) as an acceptable recipient of the occupied zone-- an idea believed to be attractive to President-elect Ronald Reagan.
One way in which Jordan might extricate itself from the shadow of Syria's Soviet-supplied artillery and tanks (1,200 of the latter reportedly deployed near Dara along the southeastern frontier of Syria) would be to profess adherence to tht views of the "rejectionist front" -- against the Camp David accords and the US-backed peacemaking process.
Disclosures to the effect that Jordan already and consented to keep out of the bargaining over West Bank control have been firmly denied in Amman, however.
The most forthright expression of Israel's attitude toward events in the Arab world came from former foreign minister Moshe Dayan in an impromptu interview conducted in the Knesset (parliament) building.
He dismissed the importance of inter-Arab disputes, saying, "The Palestine problem is our main concern regardless of other developments.
Mr. Dayan termed such things as the Jordanian-Syrian confrontation as "mere passing interludes," noting that the Palestinian problem is constant. He observed, however, that "1980 is not 1970," intimating that what Israel did to shore up Jordan's defense while he was defense minister might not be repeated this time.
Mr. Dayan admitted that changes in Jordan's political framework in which the Palestinians might gain supremacy "would not necessarily be in conflict with our interests."
Yet he ruled out the notion of Israel acting to advance the plo's designs on Jordan in which Syria, as a prime PLO patron, is a primary factor.