With the Middle East launched on what could be the most destructive war it has ever known, the death of one man far from the Persian Gulf battlefield this week would seem a minor event. But the slaying of Salah Khalaf in Tunis is a turning point for the Palestinian movement and a significant part of what the war in the Gulf involves for the Arab World.

Khalaf is the Palestinian guerrilla chieftain better known as Abu Iyad. He would not have expected nor wanted his death to produce lamentations in the Western press, nor does it merit any. Khalaf was a realist. That is no doubt why he was slain by a Palestinian gunman in Tunis.

Khalaf appears to have been the victim of the internecine war between his Fatah organization and the Abu Nidal gang of killers, who are now allied with Iraq. Whether Khalaf's increasingly open differences with Baghdad and PLO leader Yasser Arafat over Arafat's alliance with Saddam Hussein were a factor in the killing can only be a matter of speculation at this point.

But those differences have everything to do with the broad political meaning of the Gulf war for the Middle East. Khalaf had emerged as a serious spokesman for those Palestinians who recognize the bankruptcy of Arab politics and who try to forge a new national identity that seeks peace with Israel. That branded him as a danger for those like Abu Nidal and his patron, Saddam Hussein, who fight to hold the Arab World prisoner in its calamitous past.

To justify his invasion of Kuwait, Saddam has sought to bludgeon other Arab countries back into the embittered, dead-end concept of Arab nationalism that has prevailed since 1948.

But the invasion of Kuwait shocked leaders in Egypt, Saudi Arabia and elsewhere into finally rejecting the Arab pretense, which had already been undermined by the Palestinian uprising in the West Bank and Gaza Strip territories.

Saddam has dragged the Arab world into a war that will destroy its existing political contours. This likelihood frightens an Arabist establishment in America and Europe that tended to make excuses for Saddam and opposed action against him in hopes that somehow the old order can be salvaged.

In an interview with an Arab journalist that was published in Algeria on Monday, the day of his assassination, and in the Paris daily La Croix on Tuesday, Khalaf indicated that he saw the alliance with Iraq as a fatal mistake for the PLO -- at a time when Arafat was in Baghdad proclaiming that "Palestine and Iraq are in the same trench."

"I don't want my own cause associated with the destruction of the Arab region," Khalaf said. "We are really caught between two fires."

Moreover, he disclosed that Iraq had "ignored" the PLO's own peace initiative, which called on Saddam to make some statement about Iraqi withdrawal from Kuwait in return for a United Nations statement establishing a link between the Palestine problem and the Persian Gulf. "Both parties ignored our peace proposal," Khalaf said.

Not even to the PLO did Saddam show interest in a compromise involving the "linkage" formula. To the end, Saddam remained consistent, cynically putting the Palestinian issue forward to distract attention from his crimes while refusing to make any sacrifice for the Palestinians. Arafat goes along like Mr. Micawber, hoping something will turn up. Khalaf's death removes the serious center of the PLO leadership.

When I saw him in Tunis a little over a year ago, Khalaf had just embarked on a campaign to stamp out the renegade Abu Nidal group. Abu Nidal had targeted Palestinians willing to deal with Israel and with the United States and accept a truncated Palestinian state. Khalaf hoped that by working through defectors he could destroy the gang; instead one of the defectors killed him.

Khalaf admitted then that his own turn from terrorist campaigns to calling for peace talks between Israelis and Palestinians resulted from the failure of the old, discredited form of Arab nationalism the PLO nurtured in exile. "It is the intifada which imposed this on us. Seeing children risking their lives imposed on us the need to achieve a realistic peace."

A similar view was put with far more eloquence in a remarkable commentary by the Palestinian-American writer Edward Said published by The New York Times Jan. 11. While strongly criticizing America's willingness to resort to war to oust Saddam from Kuwait, Said accurately portrayed what Saddam is up to in seeking to perpetuate an Arab world "with its terrible inequities, its self-inflicted wounds, its crushing mediocrity in science" and other fields:

"It is as if Mr. Hussein had collected all the tattered remnants -- anger at colonialism, despair at being unable to deal with the challenge of Israel, noble rhetoric about Arab honor -- and forced them into a row of banners people will salute because there is little else to like or respect" in Arab nationalism today.

"Linkage" of the Gulf crisis with the Palestinian problem is a reality, not a diplomatic formula to be manipulated to save face for Saddam Hussein. There is no way to begin to deal with the Palestinian problem until the lies and brutality of the dying form of Arab nationalism have been discarded. In his folly, Saddam has made his destruction the agent of a new Arab future.