Across the Moslem world, the fallout from the Iranian revolution appears to be bringing Islamic militancy to the fore and exacerbating religious and ethnic tensions that have never been far from the surface in the volatile Middle East.

But does this upsurge of Moslem fanaticism -- evident in recent developments in Iran, the seizure of the Great Mosque in Mecca and the attack on the U.S. Embassy in Pakistan -- represent the outward signs of a fundamental, deep-seated conflict between the Moslem world and the United States? And does it signal the eruption of a much-debated Islamic revival that will reshape the Arab world and sweep away monarchies and Western-oriented leaders?

In the view of some Islamic scholars here, the rise of fanatical Moslem elements owes more to internal tensions in their countries caused by poorly managed modernization and bad government than to any burgeoning of Islamic revolution or inherent enmity toward the United States.

The anti-Americanism associated with the current upsurge of extremist Moslem sentiment is seen as resulting from three basic factors: the long U.S. support for Israel, the close ties between the United States and the deposed secular regime of the shah in Iran and the perception in many countries of America as the symbol of pervasive Western culture and influence.

There is no consensus on how deep this anti-American sentiment goes. Some scholars see it as largely a product of the times and the ills that have accompanied the industrialization efforts of many Moslem countries.

"I don't see Islam as inherently anti-American," said John Ruedy, a professor of Islamic studies at Georgetown University. He said the recent rise of Moslem zealots represents "the frustration inherent in an attempt to industrialize rapidly."

The failures of some of these efforts, social inequities and unbalanced distribution of wealth, and the inability of governments to meet high popular expectations, especially in oil-producing countries such as Iran, have contributed to "a phase of stock-taking," Ruedy said.

Whether the connection between rising Islamic fanaticism and violent anti-Americanism is temporary or not, there does seem to be an eagerness among many zealous Moslems to blame the United States for whatever misfortune arises.

This was illustrated by an attack yesterday on the U.S. Embassy in Islamabad, Pakistan, by militants who linked the United States with the seizure Tuesday of the Great Mosque in Mecca.

Iran's Ayatollah Ruhollah Khomeini also drew this connection, despite indications that the impetus for the takeover of Islam's most sacred shrine may have come from closer to home.

The initial Saudi version of the incident -- specifically the attackers' alleged demand that worshippers recognize "one of their number" as the "mahdi" or Islamic messiah -- tentatively pointed to Shiite Moslems as the perpetrators, although this was by no means certain. Shiites, who predominate in Iran where Khomeini is the leader of the faith, believe that a descendant of the prophet. Mohammed, the 12th imam, will return to save the world. Some Sunni Moslems also believe in a "mahdi," but the concept is not central to the faith as it is in Shiism.

An Egyptian truck driver who said he witnessed the attack quoted a Saudi as saying that the attackers came from the Gizan area near the Saudi border with North Yemen.

In fact, North Yemen has a large Shiite Moslem population and was run by a Shiite clergyman until a secular government took power.

Regardless of the identity of the attackers, there seems little doubt that the Iranian revolution has encouraged Moslem fanatics in other countries to test their power. This has aggravated the kind of religious, political and economic turmoil in the Middle East that exploded in the 1975-76 Lebanese civil war and has been bubbling ever since.

Another Egyptian witness said the attackers claimed to belong to the Qoraish tribe, from which the prophet Mohammed was descended. If true, this would indicate that the attackers were extremist Sunnis.

Following agitation by Shiite clergymen in Khomeini's entourage, demonstrations and disturbances have been reported in Arab sheikdoms along the Persian Gulf. In Saudi Arabia, worried local authorities have tried to keep Iranian pilgrims on a tight leash, and Iranian supporters of Khomeini have complained of harassment.

Khomeini's influence also has spilled over into Lebanon, where Shiites make up the largest sect in a country sharply divided along sectarian lines.

Shiite followers of Khomeini also have grown restless in Iraq and Lebanon, which have large Shiite populations.

Moreover, the kind of Islamic fundamentalism that Khomeini represents has galvanized factions of zealots in most other Arab countries, including Syria and Egypt where branches of the Moslem Brotherhood oppose the government.

However, there is a long way to go before Khomeini and like-minded militants realize the dream of uniting Moslem countries under a single fundamentalist Islamic leadership. This idea runs up against the nationlism that has thwarted attempts for Arab unity in the past, not to mention the loftier goal of Islamic unity.

In expressing concern about a U.S. reaction against Moslem countries on an across-the-board religious basis, Arab diplomats here have gone out of their way in contacts with U.S. officials to repudiate Khomeini-inspired actions despite the bonds of Islam. "We represent countries, not religions," one diplomat said. "Our country is a Moslem state, but Islam has nothing to do with our diplomatic relations."