After four weeks of fighting, two essential facts in the familiar good news/bad news pattern stand out about the Persian Gulf war between Iraq and Iran.

First, the worst has not happened. The flames of battle have not spread to the other oil-producing nations or the narrow strait of the world's most economically vital region, and a military confrontation involving outside powers, including the United States and the Soviet Union, has not occurred. In recent days, in fact, Washington officials have downgraded the likelihood of such calamities.

Second, however, is the fact that no settlement of the conflict has taken shape or is even projected by Washington policy-makers. Meanwhile, the war's impact on the world's oil production continues to be substantial, and the threat persists of greater dangers ahead involving the combatants, their Persian Gulf neighbors, the superpowers and the oil supply of the developed West and Third World nations alike.

The Iran-Iraq war, four weeks old today, has been called a war of attrition, a war of exhaustion, a war of miscalculation. All this may be true. It also is a war with unusually serious repercussions for other nations.

Like a stone thrown into a pond, this war has produced ripples visible from afar as a series of widening concentric circles. This is because the pond, in this case, is the Persian Gulf, the most important source of available petroleum for an oil-short world.

In its most basic dimension, the war is the latest episode in a border dispute, complicated by ethnic antagonisms, that has festered for centuries. Fighting over the Shatt-al-Arab waterway involving the town of Khorramshahr (then known as Muhammarah) dates back to an 1837 battle between the Ottoman Turks (then inhabiting the Iraqi side) and the Persian Empire (on the Iranian side.)

Previous efforts to settle the conflict include an 1847 treaty, a 1914 border demarcation based on 1911 and 1913 agreements, a 1937 treaty and the 1975 Algiers agreement that was repudiated by Iraq this Sept. 17, leading to full-scale war five days later.

There are many such unresolved border and ethnic conflicts in the world of nation states. To name only a few: the battle between Somalia and Ethiopia in Africa, between Israel and its Arab neighbors in the Middle East, between Argentina and Chile in South America, between Vietnam and Cambodia in East Asia. Last week an 11-year-old border war between Honduras and El Salvador was settled with a peace treaty that rated six inches on an inside page of The Washington Post. p

Some of the other local disputes are of serious international importance because of the actual or potential involvement of outside powers. But none is so fraught with immediate peril to the resources that power the turbines and engines of the modern world.

The latest eruption between Iraq and Iran had been building for many months. The underlying causes, in the view of Washington officials, were the radically changed balance of power resulting from the fall of the shah's government in Iran and the emergence of a more powerful Iraq, and the fear among Iraq's leaders that the political fervor of revolutionary Iran could spread to their populace. Post-revolutionary Iran, while seemingly weak militarily, was extremely provocative to its neighbor.

Serious clashes between the two countries broke out more than six months ago, and became more heated in early September. About three days before the outbreak of full-scale fighting, the CIA's National Foreign Assessment Center issued an "alert memorandum" warning of a likely Iraqi attack. No date was given for the start of hostilities.

At this point, the consensus among intelligence analysts and other specialists in the area was that Iraq would quickly and rather easily triumph over Iran. The fear in some quarters of U.S. intelligence was that Iran would quickly fragment, providing a golden opportunity for Soviet expansion.

To nearly everyone's surprise, Iran fought back effectively. Iranian President Abol Hassan Bani-Sadr has claimed that his country had advance intelligence of the Iraqi attack, enabling it to make secret plans to resist. Whether or not that was the case, it is clear that Iraq, as President Saddam Hussein is reported to have conceded in private, did not expect or prepare for as much resistance.

Another early casualty was the belief in Washington, Moscow and several other capitals that the two combatants would refrain from attacking one another's oil facilities to preserve their basic national assets. Iran, followed by Iraq, violated this theory early. Oil fields, pipelines, refineries, loading terminals and other such facilities have been prime targets, suffering serious damage as each side went for the jugular. b

The Persian Gulf war seems to be settling down to a stalemate. Iraq apparently has the power to punish Iran economically and politically, holding key positions inside the Iranian oil province of Khuzistan, but not the power to bring down the Khomeini regime or to force Iran to sue for peace. Iran apparently has the power to penalize Iraq with air strikes, sabotage and other forms of resistance, but not the power to expel Iraqi troops from Iranian territory.

Neither side can win, in the view of Washington officials. But there is also no sign that either side is ready to compromise, much less capitulate. According to current estimates here, both sides are capable of continuing the battle and seem likely to do so for a matter of months at a damaging if possibly declining level of intensity. This estimate is based on the military supplies the two sides have today.If supplies are augumented from the outside they could do more.

The consequences of what has happened so far, and projections of the future, are not easy to assess. Here, as best they are known today, are some of the repercussions:

The narrowly based Iraqi regime headed by Saddam Hussein has failed to win the glorious national victory it had expected, and instead has plunged the country into a costly war that may drag on for many months. Before the war Iraq was a well-functioning and increasingly prosperous and powerful country, and thus it and its leaders have much to lose as a result of the war.

Iran's revolutionary Islamic regime has fought better than expected, particularly in the air, and the battle against the invaders has temporarily united the country in a new nationalistic fervor. But the economic damage has been severe, and could worsen. For the first time since the revolution, Iran must increasingly look to the outside world for military and political support. The U.N. mission of Prime Minister Mohammed Ali Rajai is only the first consequence of this need.

The 52 American hostages have become even more of a practical liability to Iran, as the international embargo and financial freeze imposed by many nations make it difficult for Iranian agents to obtain needed parts and supplies. U.S. officials believe there is a fairly wide consensus in Iran that the hostage problem should be ended, but there is yet no known consensus about the terms and conditions for doing so.

The other oil-producing states of the Persian Gulf, particularly the petroleum blue chip, Saudi Arabia, have experienced severe shocks and new military and political strains. The Saudi state has agreed to increase its oil production to compensate for the loss of Iranian and Iraqi exports of the world market, and it has turned to the United States for defensive military assistance in the form of U.S. Air Force radar warning and control planes. Both increased oil production and a U.S. military presence have been controversial inside the country in the past. New internal and external strains add to an already tense Saudi environment in worrisome fashion.

The superpowers, the United States and the Soviet Union, have warned each other privately and publicly against becoming involved in the battle. The United States fears an enhanced Soviet military and political position in this strategic region, while the Russians fear that the United States will use the war to recoup the position that was lost with the fall of the shah. So far both sides have cautiously remained aloof from the battle, but over time the temptations are likely to become stronger to become involved, at least as arms suppliers, in the face of the combatants' growing needs.

The oil-consuming world has looked on with dismay as about 3.7 million barrels per day of petroleum exports were disrupted by the war. Iran continues to export a small amount of oil through Lavan Island, but all production by Iraq has been shut down. The temporary world oil surplus built up in recent months, plus the increased production by Saudi Arabia and others, shielded the international market from the immediate effects of the cutbacks in Iraqi and Iranian exports. But if the conflict continues as expected, the market could feel the pinch, imposing a new round of price increases on a world that has yet to adjust to the redoubling of oil prices in 1979.

The dangerous prospects affect not only the two combatants but also, directly or indirectly, most of the other nations on the globe. That is why, even though the worst has not occurred in these first four weeks, policy-makers in Washington and many other capitals find little grounds for comfort or complacency in the course of the war in the Persian Gulf.