The Iranian Army's sudden capture of the vital port city of Khorramshahr has dealt a stunning blow to Iraq and its Arab allies.
The end of the 20-month-old Gulf war, which Iranian sources say is now all but accomplished, is coming much more quickly -- and much more to the detriment of Iraq and the conservative, Sunni Muslim governments of the Arab world -- than anyone had calculated. And the repercussions may reach far beyond the swampy lowlands of the Shatt al Arab.
Because of Iran's swift victory at Khorramshahr this week, almost all Arab promises of eventual aid to Iraq have been rendered academic, unless, of course, Iran presses its victory by crossing into Iraq.
If that happens, Jordan, Morocco, Saudi Arabia, and Egypt might send troops to join the fight against Iran. But if Iran stops at the international border agreed on under the Algiers Treaty of 1975, it will have carried the day over Iraq and would be in position to reinvoke the treaty.
Baghdad May 25 admitted the loss of Khorramshahr, saying the Iraqi Army had ''withdrawn'' and was taking up positions at the ''international border.'' Iran said it captured the city May 24, taking some 12,000 Iraqi prisoners and having killed the Iraqi commander.
So shocked has been the Arab world that the leaders and their news agencies have been abnormally quiescent. It is as if the pro-Iraqi regimes are still trying to determine the extent of Iraq's defeat and measure the probable Iranian response if they now make an overt show of support for Iraq.
The bellwether among these Arab countries is Kuwait. If Kuwait opts to aid Iraq more openly, it could well come under Iranian military attack. Last week Iranian Prime Minister Mir Hossein Musavi warned Kuwait not to interfere.
If Kuwait is attacked, then the other five members of the Gulf Cooperation Council (Saudi Arabia, the United Arab Emirates, Bahrain, Oman, and Qatar) would be likely to enter the fray.
Last week, Saudi Arabia's government-controlled Riyadh Radio bravely warned Iran it was committing ''a grave error'' if it believed the Gulf Arabs were frightened of Iranian attack. If Kuwait is in peril, the Saudi radio said, other members of the GCC would ''know the meaning of collective responsibility when a GCC member is exposed to a threat.''
But as of this writing, Kuwait had not committed itself to any higher level of assistance to Iraq.
For the past few weeks, the Arab moderates have been preparing themselves for an Iranian victory in the Gulf war, though they hardly expected it to occur so soon. Anticipating Iran's capture of Khorramshahr, Cairo radio said the ''extremely grave threats'' from Tehran ''confirm the worst fears of the Gulf states -- namely that Iran is serious about its plans to export its Islamic revolution. Since the Iranian-style Islamic revolution is rejected by the Gulf states, this plan involves a direct threat to their Arabism and independence.''
The conservative, Sunni Arab countries are seizing on Iran's bellicose talk of spreading the Islamic revolution as the real reason Iraq went to war in September 1980 and the reason they might have to make common cause with Iraq. The December 1981 coup attempt in Bahrain by Iran-backed Shiites has given them some inkling of how Iran might export its revolution - that is, by instigating the Shia Islamic communities throughout the Arab world.
But short of a direct Shiite-Sunni religious conflict, there is an important territorial issue at stake. Iran claims it has the historical right, as heir to the Ottoman Empire in this part of the world, to full sovereignty over the Shatt al Arab waterway. This waterway is used by both Iraq and Iran for reaching the oil refineries at the north of the Gulf by ship. Iraq claims sovereignty should be shared.
To strictly neutral observers, what Iran has achieved up to now has been the reoccupation of territory that the 1975 Algiers treaty agreed belonged to Iran and that Iraq seized in late 1980. Iraq claimed the treaty was signed under duress, since the late Shah of Iran was aiding Kurdish insurgents in Iraq at the time and agreed to stop this if the Iraqis signed the treaty.
Observers say there is little doubt that, regardless of Iraq's justification, it was the Iraqi Army that turned the bickering and occasional artillery duels over the Shatt al Arab waterway into a full-fledged war.
In the weeks ahead, Arab eyes are sure to be on the remaining slices of Iran held by Iraq. If they are vacated or -- more likely -- overrun by Iranian soldiers, that will bring attention again to the 1975 boundary. If Iran pushes beyond that boundary, then the Middle East risks a serious escalation of the war. This could endanger oil refineries, pipelines, and tanker ships -- so vital to the Western world's energy needs -- all along the Gulf.
If Iran halts at the border, however, it seems possible that the prewar status quo could be effected. But given the latest demands of the victory-heady Iranian leaders, status quo may not be enough of a victory. Iran is demanding not only that all Iraqi soldiers be withdrawn, but that Iraqi leader Saddam Hussein must be overthrown, that Iraq must pay reparations, and that some 100, 000 expelled Iraqi Shiites be repatriated.