Foiled PLO attack still pays dividends for Yasser Arafat. Guerrilla attempt in Israel boosts tough image of Arafat faction

Guerrillas of Yasser Arafat's Al-Fatah faction of the Palestine Liberation Organization gave their leader an important boost by infiltrating Israel's northern border on the eve of the Palestine National Council's (PNC) meeting. The PNC session, which began yesterday in Algiers, is expected to result in reunification of the splintered PLO, a goal cherished by most Palestinians but fraught with dangers for Mr. Arafat.

By reconciling with hard-line, leftist Palestinian factions, the PLO chairman risks losing his ability to maneuver on the Arab and international scenes. He also dims already bleak chances of working toward a peaceful settlement of the Palestinian problem.

Leaders of the leftist Democratic Front and the Popular Front for the Liberation of Palestine have been relentlessly pressuring Arafat to back away from his diplomatic efforts and rededicate himself to military struggle against Israel. Arafat has been trying to meet the minimal demands of the hard-liners while preserving as much as possible of his freedom to act.

Against such a backdrop, Fatah's successful penetration of Israel's multi-million-dollar, northern border defenses can only strengthen Arafat's position during the tough negotiations expected at the PNC meeting.

It will matter little to the Palestinians at the PNC that the trio of guerrillas who crossed into Israel near a border kibbutz early Sunday morning were discovered almost immediately and killed by an Israeli patrol. What is important is that they claimed the lives of two Israeli soldiers before they themselves were killed.

For Palestinians in Algiers, such a clash between Palestinian guerrillas and Israeli soldiers inside Israel serves as an impressive reminder that Arafat's Fatah organization still is capable of planning and carrying out bold, imaginative attacks against the Israeli Army. It will do much to silence Palestinian critics who accuse Fatah of degenerating into a top-heavy, well-fed bureaucracy that has lost touch with its founding purpose - the armed struggle against Israel.

The Israeli military described the clash as one of the bloodiest infiltrations from Lebanon into Israel in years. Within hours of the attack, the Israelis charged that leaflets discovered on the guerrillas linked them to Fatah and indicated they had planned to take hostages and exchange them for Palestinian prisoners. Fatah itself claimed responsibility for the infiltration.

By Sunday evening, the Israelis had launched an air strike against what an Army spokesman described as a launching base for PLO fighters in a Palestinian refugee camp near the Lebanese port of Tyre.

The PLO infiltration was the sort of operation Arafat could be fairly said to dream of executing. Ironically, its failure could be seen as one of its advantages, if the Israelis are correct that the purpose was to take civilian hostages. Attacks that involve civilians are problematic - both in the eyes of some Palestinians and of much of the international community. But an attack against soldiers is viewed as legitimate by the broadest spectrum of Palestinians and by a large part of the world community.

Such an infiltration involves complex logistics and substantial training to get guerrillas across Israel's self-proclaimed ``security zone,'' which stretches above the border six miles into Lebanon and is jointly patrolled by Israeli troops and the Israeli-backed South Lebanon Army militia.

The zone is rife with Israeli undercover agents and a network of informers. The border fence is protected by a maze of mines, tank traps, and electronic-sensing devices. But it appears that the Fatah guerrillas went undetected until they actually had crossed the fence.

In politicized Palestinian circles, such a penetration is the stuff of which martyrs are made.