BAGHDAD, IRAQ, SEPT. 6 -- Iraqi President Saddam Hussein's born-again appeal to fundamentalist Islamic sentiments has startled many observers of his government, who recall that his ruling Baath Party was founded on strongly secular principles of Arab unity and modernism -- largely in opposition to the traditional Islamic culture that Baathist thinkers felt had held back the Arab world.

But Saddam's Islamic rhetoric, whatever the inconsistencies, seems to be working with many ordinary Iraqi Moslems. Saddam's success is typified in the attitudes of Baghdad resident Maan Qaiso.

Throughout the Iran-Iraq war, for eight long and bloody years, Qaiso was reluctant, but ready to fight on. He was ready to postpone taking over the family clothing store in Baghdad. With regret, he was even ready to postpone marriage and getting started with his life.

Now, only two years after coming home from war and seven months after finally getting married, Qaiso said he is even readier to respond to Saddam's latest call to arms. This time it is an even worthier cause, he declared, because the struggle is against American "infidels" who the Iraqi leader says have desecrated Moslem holy places in Saudi Arabia.

"It is different because the Iran-Iraq war was killing fellow Moslems," Qaiso explained. "It was like killing your brother. But in this one, Americans and Englishmen are in Mecca, and this is bad. All Iraqis will be motivated to fight them."

Iraq's claim that Western troops are in Mecca is false, according to U.S. and Saudi officials. But for Qaiso and untold numbers of his fellow Moslems here, Saddam has translated the Persian Gulf confrontation into a struggle between Islam and the West. The man whom Washington aided in the 1980s as a bulwark against radical Islamic revolution has suddenly begun to stir those very forces in search of support against the United States and its allies.

Saudi Arabia, which poured billions of dollars into Saddam's war chest to help him fend off Iran's extremist Shiite Moslems, has become in the Iraqi leader's lexicon a den of corruption that has sold out its Islamic purity for luxury and protection from the United States. In several speeches, Saddam has called on the people of Saudi Arabia -- particularly the Shiite underclass in the east -- to rise up against King Fahd and his House of Saud for failing in their mission to guard Mecca.

The Baath Party constitution, however, states: "The educational policy of the party aims at the creation of a new Arab generation that believes in the oneness of the Arab nation and of the permanence of its mission, a generation that welcomes scientific thought and that is free of the bonds of superstition and of retrograde tradition."

In a reflection of this policy, Iraq has taken its place among the Arab nations freest from traditional Islamic strictures. Alcoholic beverages are sold freely. Women in the cities attend school, work and dress as they please. They frequently respond to men's admiring glances by returning the gaze unflinchingly and smiling in a way rarely encountered in more traditional Moslem countries.

In many ways, the Iran-Iraq war broke out because Saddam judged that his country's forced march toward modernity was jeopardized by the rise of Islamic fundamentalism in neighboring Iran. Although the Baath leadership is largely Sunni Moslem and the country embraces a range of other religions, Iraq's population of 17 million includes a slight majority of Shiites who seemed inclined to listen to the radical preachings of Iranian mullahs.

Now, one Western diplomat observed, Saddam has begun to sound like a mullah himself. A rousing message from Saddam Wednesday night, addressed to "Moslems wherever you are," contained language that could have been taken from a Friday prayer session in Tehran.

"Allahu akbar," intoned an announcer when he finished reading the message on television. "God is greatest, God is greatest, God is greatest."

Saddam's message repeatedly called on "the faithful" to back Iraq in what he depicted as "the struggle of the era," pitting "infidels" from the West against an Arab Moslem army with Iraq at its head. Because of their association with the United States, he said, Fahd and President Hosni Mubarak of Egypt have "strayed from the path of God."

"This is a confrontation of justice against evil," he declared, "and a confrontation of faith against infidelity, and a confrontation between the rights of the supreme God and the devil's desire to enjoy human rights."

Saddam began making gestures toward devout Iraqi Moslems midway through the Iran-Iraq war, seeking to defuse resentment among the country's Shiite population. He made a pilgrimage to Mecca that was widely publicized with photos showing him in the traditional, seamless white pilgrim's robe. In addition, some of the countless Saddam posters in and around nearly every building began to show him kneeling in prayer.

But in several speeches since Iraq's Aug. 2 invasion of Kuwait plunged the region into the danger of war, Saddam seems to have gone beyond respectful gestures for the devout. Since the crisis began, he has, on several occasions, sought to arouse the dark strains of popular Islamic rage against his enemies by presenting himself as a protector of the faith.

"This is completely contrary to Baath Party principles," said a diplomat from a Moslem country. "But he thinks that if he can present the case as a conflict between Moslems and Christians, he can have more support. When you are cornered, you don't hestitate to use any means."

Some diplomats here have speculated that Saddam also has decided on the Islamic tactics as a lure for Iran. Alongside his religious appeal to Moslems, Saddam has presented Iraq as an Arab nationalist champion against Western imperialism, saying the Palestinian struggle also is at stake in the gulf. The U.S. military presence in Saudi Arabia has been depicted as a return of British colonial rule that held sway in the region for half of this century and whose heritage has contributed to many conflicts here since independence.

These traces of colonialism will be expunged from the region in the coming battle led by Iraq, Saddam predicted Wednesday night.

"Jerusalem will return after that, free and Arab," he pledged, "as the center of faith and the faithful. And Palestine will be liberated from the Zionist yoke. And a sun that never sets will shine on Arabs and the Islamic nation."