Israel's air attack on the Palestine Liberation Organization headquarters in Tunisia on Tuesday, say western and Arab analysts here, is another example of actions by Tel Aviv that have cost the United States -- as Israel's chief supporter -- influence over the years among even the more pro-American states of the region.

"The raid against the PLO was militarily a success," said a long-time Middle East specialist, "but a political disaster for the United States."

These diplomats and analysts say that whatever the pros and cons of U.S. and Israeli policy, Washington's influence in the Arab world has been waning in tandem with the latest air raid and these previous events:

*In June 1981, U.S.-supplied Israeli aircraft destroyed Iraq's nuclear reactor near Baghdad despite the presence of U.S. Air Force electronic surveillance aircraft operating along their flight path.

*In Lebanon, the Israeli invasion of 1982 led to the involvement of U.S. marines, who then became mired in the violence of Lebanese politics and later had to be withdrawn.

In both these cases, rightly or wrongly, many moderate Arabs accuse the United States of failing to crack down on its Israeli ally, thus bringing into question more than ever their own political and military reliance on the United States.

The analysts also cite a related case, not involving any military attack, last April when president Jaafar Nimeri of Sudan was overthrown in part because he helped the United States fly Ethiopian Jews out of Sudan to Israel. Nimeri's successors are currently conducting public trials of his lieutenants involved in the exodus, to Washington's embarrassment.

In the latest incident, President Reagan has added what many citizens of Tunisia, a consistently pro-American country, describe as insult to the injury by appearing to condone publicly the Israeli air raid as a legitimate act of self-defense. They point out that Western European governments have roundly condemned it, and the State Department sought in a statement Wednesday to moderate Reagan's initial statement of support.

A foreign service officer in Tunis said many officials in the U.S. AID mission there were so dismayed by Reagan's statement Tuesday that "they want to quit or retire."

The AID official, who initiated the phone interview but asked not to be identified by name, said Reagan "put us in danger by his statement, which was stupidly worded. If loss of U.S. life occurred here, it would be his fault." The official said the AID mission spent 3 1/2 hours on the roof burning documents because "we didn't know what would happen." Noting that Tunisians seemed convinced of U.S. complicity in the raid, the official said, "On the basis of information available publicly, I would say the United States did know about the raid" beforehand.

The perception that Reagan condoned the raid has shocked many Tunisians, who long have considered the United States as a bulwark protecting them from the threat of foreign aggression.

Since Tunisian independence from France in 1956, that relationship has meant Tunis has stood up to various pressures, and most recently to threats from neighboring Libya. Habib Bourguiba, at 82, presides over a country that has been disturbed by serious violence in three of the past seven years and faces an uncertain succession after his long rule.

Symptomatic of the anti-American mood here was a call from the political opposition -- ranging from communists and moderate social democrats to Moslem fundamentalists -- to break off diplomatic relations with Washington.

With Tunisia playing host to both the 21-nation Arab League and Yasser Arafat's wing of the divided Palestinian nationalist movement, many Tunisians have concluded that the raid was intended to torpedo the stalled peace initiative launched in February by the PLO leader and King Hussein of Jordan.

In this view, a key objective was to discourage the Reagan administration from meeting a joint Palestinian-Jordanian delegation as a first step in that peace process.

Arab analysts here contended that anti-Arafat Palestinians were responsible for the Sept. 24 killing of three Israelis in Cyprus, which was the Israeli government's official justification for the raid.

These Arabs noted as a precedent the shooting of Israeli Ambassador Shlomo Argov in London in June 1982 by anti-Arafat gunmen. That attack served to justify Israel's invasion of Lebanon to drive out the PLO.