Quarreling among Yasser Arafat's enemies here appears to have strengthened the Palestine Liberation Organization chairman's hand in pursuing a negotiated peace settlement with Israel. United States Assistant Secretary of State Richard Murphy is due in the Middle East within a month for exploratory talks with a joint Palestinian-Jordanian delegation, the membership and duties of which are still to be finalized.
The formation of such a delegation, agreed to by Mr. Arafat and Jordan's King Hussein last February, has been opposed by hard-line Palestinian leaders who view it as capitulation under Jordanian, Israeli, and American pressure.
The feud that seems to be aiding Arafat is between the Syrian regime of President Hafez Assad and the radical wing of the PLO which is based in Damascus and viewed generally as pro-Syrian. It was touched off in mid-May by the crackdown of the Lebanese Shiite Muslim militia, Amal, on Palestinian guerrillas trying to reestablish themselves in former strongholds in Beirut. Syria supported Amal's attack, which resulted in a month-long siege of three Palestinian refugee camps that left nearly 600 people dead.
Syria was immediately, and sometimes sharply, criticized by the Palestinian guerrilla organizations based in Damascus. These included the breakaway Al-Fatah faction led by Col. Saeed Musa, known as Abu Musa, and the two leading Marxist factions, the Popular Front for the Liberation of Palestine, lead by George Habash, and the Democratic Front for the Liberation of Palestine. An Amal-PLO agreement to stop the fighting in Beirut was brokered by Syria last month. But some Palestinian officials here say they signed it only to halt the bloodshed in Beirut and they do not feel bound to the provisions intended to curb PLO activities in Lebanon.
Arafat's position among Palestinians has been enhanced because the Syrian regime's heavy-handed effort to control the hard-line wing has discredited it as a true friend of the Palestinians, some Palestinian officials say. Some PLO officials in Damascus also say that the rift with Syria could pave the way for a rapprochement between Arafat and his hard-line opponents. The anti-Arafat revolt in 1983 drove the PLO leader from his last remaining Lebanese stronghold, in Tripoli.
But, the Syrian-based PLO officials say, a mending of ties would not occur until Arafat abandoned his peace moves with the Jordanian monarch. In February, Arafat agreed generally to the ``land for peace'' formula for negotiations embodied in United Nations Resolution 242, which the US strongly supports. King Hussein, the claim, will try to dominate the PLO even if the Israeli-occupied West Bank and Gaza Strip are regained through peace negotiations with Israel.
Meanwhile, it is plain that relations between Syria and the hard-line PLO wing remain severely strained. Syria banned all six PLO periodicals published in Damascus after they attacked Syrian policy, and only two have been allowed to resume distribution. A Western aid official said tensions continue to be high in Palestinian refugee camps in Syria. Plainclothes Syrian intelligence men have increased their presence in refugee shantytowns, on apparent guard against an anti-Syrian uprising.
The quarrel is likely to continue because of incompatible objectives sought in Lebanon by the Assad regime on the one hand, and hard-line PLO guerrillas on the other.
Syria is embarking on a new version of its ``Pax Syriana'' -- an attempto stabilize the situtation in Lebanon so as to preserve maximum Syrian leverage there.
First Syria wants to end hostilities among Muslim militias in west Beirut and thereby cool off tensions that have arisen between Shiite and Sunni Muslims. Afterward, the Assad regime wants to bring the Muslim and Christian leaders together for genuine national reconciliation talks, according to Syrian officials. These talks would lead to a new constitution that would end Christian supremacy in Lebanon's political system and give greater representation to the Shiite community.
The hard-line PLO wing, however, wants to reestablish itself in Beirut and southern Lebanon for agitation against Israel -- a strategy that would not bring about the stability that Syria has emphatically declared as its objective. According to an official from the Popular Front for the Liberation of Palestine (PFLP), Palestinians are counting on two old Lebanese allies for help in regaining a measure of the PLO's former autonomy in Lebanon: Druze chieftain Walid Jumblatt, who did not participate in Amal's attack on the PLO in Beirut, and Mustafa Saad the Sunni militia leader in Sidon.
Many of the Damascus-based PLO leaders strongly disagreed with Arafat's decision in 1982 to accept a US-mediated plan to evacuate some 14,000 PLO fighters who were under siege by the Israeli Army. In Palestinian circles, they have blamed Arafat for the subsequent massacre of Palestinian refugees in the Sabra and Shatila camps which took place after the PLO guerrillas left.
``We are trying to strengthen our military position in Sidon,'' said the PFLP official. ``For now, we want to protect ourselves, the Palestinians in the refugee camps, against any more attacks by Amal. But ultimately we want to continue the armed struggle against Israel.''
As a result of the differences the Syrian-sponsored Palestinian National Salvation Front, has all but collapsed. Containing most of the Damascus-based PLO groups, it was formed in March to develop a political counteroffensive against the Arafat-Hussein moves toward talks with Israel. The crumbling of the Salvation Front may end the kind of coordination by Syria and PLO hard-liners that blocked the 1983 moves by Arafat and Hussein to negotiate with Israel under the auspices of President Reagan's 1982 Middle East peace plan.