But, she said, her life changed in 1979 when she was a medical student at the University of Aleppo, in northern Syria. At that time, the radical Muslim Brotherhood was using terrorism to try to undermine the government of President Hafez al-Assad. Gunmen of the Muslim Brotherhood burst into a classroom at the university and killed her professor as she watched, she said.

"They shot hundreds of bullets into him, shouting, 'God is great!' " she said. "At that point, I lost my trust in their god and began to question all our teachings. It was the turning point of my life, and it has led me to this present point. I had to leave. I had to look for another god."

She and her husband, who now goes by the Americanized name of David, laid plans to leave for the United States. Their visas finally came in 1989, and the Sultans and their two children (they have since had a third) settled in with friends in Cerritos, Calif., a prosperous bedroom community on the edge of Los Angeles County.

After a succession of jobs and struggles with language, Dr. Sultan has completed her American medical licensing, with the exception of a hospital residency program, which she hopes to do within a year. David operates an automotive-smog-check station. They bought a home in the Los Angeles area and put their children through local public schools. All are now American citizens.

BUT even as she settled into a comfortable middle-class American life, Dr. Sultan's anger burned within. She took to writing, first for herself, then for an Islamic reform Web site called Annaqed (The Critic), run by a Syrian expatriate in Phoenix.

An angry essay on that site by Dr. Sultan about the Muslim Brotherhood caught the attention of Al Jazeera, which invited her to debate an Algerian cleric on the air last July.

In the debate, she questioned the religious teachings that prompt young people to commit suicide in the name of God. "Why does a young Muslim man, in the prime of life, with a full life ahead, go and blow himself up?" she asked. "In our countries, religion is the sole source of education and is the only spring from which that terrorist drank until his thirst was quenched."