The Reagan administration is under conflicting pressures about how to react to the threat to the stability of the oil-rich Gulf after Iran's victory over Iraq at Khorramshahr.
There is no doubt that the United States is deeply concerned about what could happen next -- whether it be the crossing into Iraq of the victorious Iranian Army or an upsurge of Iranian subversive activity in the oil-producing conservative Arab states of the Gulf.
A minimum further aim of the Iranians would seem to be the overthrow or at least public humiliation of Iraqi strong man Saddam Hussein, who made such a mistake in launching his war against Iran in September 1980.
Already a three-way squeeze is on the US in an effort to influence its decisions about how to counter the destabilizing effect of any new move by Ayatollah Khomeini to thrust his brand of Islamic Shia fundamentalism beyond the present borders of Iran.
At issue is just how far and how the Reagan administration should intervene to try to preserve the status quo in the Gulf.
The most powerful pressure on the administration is coming from Israel and its supporters within the US. The aim of the Israelis is to head off any drawing closer of the US with Saudi Arabia or any supply of US arms to any member of the Arab camp feeling threatened by Iran. Of immediate concern to the Israelis is the possible sale to Jordan of F-16 jet fighter planes and Hawk mobile ground-to-air missiles.
In anticipation of what was coming, the executive director of one of the most powerful pro-Israel lobbying groups in Washington, Tom Dine of the American Public Affairs Committee, was already earlier this month speaking of ''a virtual explosion of Jewish political activity'' throughout the United States.
Ironically on the same side of the fence as Israel is the hard-line Arab ''steadfastness and confrontation front'' made up of Syria, Libya, Algeria, South Yemen, and the Palestine Liberation Organization (PLO). This is the most obdurately anti-Israel grouping in the Arab world. Its members share Israel's determination to keep the US away from a closer alignment with Saudi Arabia and the Arab conservatives and moderates.
Syrian President Hafez Assad said in Damascus May 25 that the situation in the Middle East had never been more dangerous. It had been brought about by US efforts to impose its domination on the area.
At a meeting of steadfastness front foreign ministers in Algiers May 24, Algerian Foreign Minister Ahmed Taleb Ibrahimi urged Arab states to deny use of their territory to the US Rapid Deployment Force. He also warned ??them against being lured into accepting the peace process between Egypt and Israel.
Pulling in the opposite direction from Israel and the Arab radical hard-liners are Saudi Arabia and those Arab conservatives and moderates. They virtually all look to the US as their ultimate protector.
Crown Prince Fahd of Saudi Arabia said May 25 that continuation or expansion of the Gulf war would be a major threat to the security and stability of the region. It could lead to the destruction of the area's energy sources. The prince was obviously hoping that President Reagan was listening.
Also addressed to the US was the statement issued after the weekly meeting of the Israeli Cabinet May 23. It said Prime Minister Menachem Begin had told the Cabinet that US Secretary of Defense Caspar Weinberger had ''misrepresented the facts'' to justify the US plan to supply weapons to Jordan. The prime minister was quoted as dismissing as ''lip service'' Mr. Weinberger's reaffirmation of the US commitment to maintain Israel's qualitative edge over the Arabs in weaponry.
Israeli Defense Minister Ariel Sharon is in the US this week and saw Mr. Weinberger in Washington May 25. Mr. Sharon said he had spoken in the srongest terms against the supply of US arms to Arabs.
''The new coalition (against Iran) -- which might be backed by the US -- based on Iraq, Jordan, and Saudi Arabia, with the support of Egypt, is a threat to peace,'' Mr. Sharon said.
At least 45 of the 100 members of the US Senate have put their names to a resolution urging the administration to cancel its proposed sale of fighter aircraft and missiles to Jordan unless Jordan agrees to enter peace negotiations with Israel.
Jordan has been Iraq's most active supporter in the Arab world in the war with Iran. It has a common border with Syria, Iran's most outspoken Arab backer in the conflict. (Syrian President Assad is a member of the Alawite sect, an offshoot of Shia Islam -- the religion of Ayatollah Khomeini -- whereas all other Arab heads of government are Sunni Muslims. Mr. Assad has long been daggers-drawn with Iraqi leader Saddam Hussein because of fundamental differences in political ideology.)
Jordanian King Hussein fears that Iran's gaining of the upper hand in the Gulf war may encourage Mr. Assad to increase his pressure on Jordan. Jordanian Crown Prince Hassan, on a visit to the US, met with US Secretary of State Alexander M. Haig Jr. in Washington May 25 and restated Jordan's case for getting US arms.
Prince Hassan put Jordan's case in an address to the Middle East Institute the same day he saw Mr. Haig. In that address he spoke of the threat to Jordan from Israel as well as from Syria. Israel, he said, was a ''regional, nuclear-capable superpower'' with a military edge over the entire Arab world. ''There is a danger,'' he argued, ''of Jordan being militarily overwhelmed.''
But Jordan will not get the US arms it wants if Israel and its lobby in the US can help it. They are determined not to be defeated on the arms-for-Jordan issue as they were defeated on the arms-for-Saudi Arabia issue in 1978 and again in 1981. In 1978, they failed in their efforts to get Congress to block the Carter administration's sale of F-15 fighter aircraft to Saudi Arabia. In 1981, they again failed to get Congress to block the Reagan administration's sale of sophisticated AWACS radar planes to Saudi Arabia.