GENEVA – In a nearly barren apartment here, Najma Ramadan, 3, a curly-haired blonde wearing tiny bear-shaped earrings, climbed the walls one recent evening, from pipe to pipe. The little girl’s toys sat far away, in boxes in South Bend, Ind., where her father, Tariq Ramadan, was to have taken up residence in August as the Henry Luce professor of religion, conflict and peace building at the University of Notre Dame.p. Nine days before his family’s scheduled departure for the United States, Mr. Ramadan, 42, a Swiss theologian of Egyptian descent who is probably Europe’s best-known Muslim intellectual, received an urgent message from the American consul in Switzerland: Washington had just revoked the visa granted him after a security review last spring.p. Neither Mr. Ramadan, a preacher of self-empowerment to European Muslims, nor Notre Dame was offered any explanation. They have since learned that the government received some information that caused it to “prudentially revoke” the visa pending an investigation, which has yet to occur.p. But the nature of that information – is Mr. Ramadan accused of a link to terrorism, of espousing terrorism, of terrorism itself? – has not been revealed.p. “It’s still not clear to him or us who turned him down and on what grounds,” said the Rev. Edward A. Malloy, president of Notre Dame. “We have no reason to think that he’s a mole or an underground instigator. He seems to be an above ground, forthright advocate of what some refer to as moderate Islam and we see him as a really good fit for our peace institute,” the Joan B. Kroc Institute for Peace and Justice, where Mr. Ramadan was to have held a joint tenured appointment with the classics department.p. For years Mr. Ramadan, a trim, telegenic man with a soft, measured voice who condemns the use of violence in the name of Islam, has been chased by allegations that his public face of moderation conceals an extremist core.p. Mr. Ramadan is the grandson of Hasan al-Banna, one of the most important Islamist figures of the 20th century, and for many of his detractors that alone makes him suspect.p. It also gives him a considerable platform, and in Europe, Mr. Ramadan is not just a professor but a high-profile intellectual who has produced 20 books, hundreds of articles and scores of lecture tapes that are hot sellers in Muslim immigrant communities.p. In much of his work, Mr. Ramadan tries to define a blended identity for Muslims in the West, arguing that one can be both fully Muslim and fully Western. His message to European Muslims is: reject your feelings of victimization, take part more fully in your countries of residence and demand your rights.p. That message has been perceived as threatening by some Europeans who fear that a growing Muslim population will lead to the dilution of national identities or the Islamization of Europe.p. Further, Mr. Ramadan’s pungent political views have antagonized a diverse lot, from French intellectuals to Egyptian government officials, from supporters of Israel to Saudi clerics.p. “When you are trying to create bridges, you are in the middle,” Mr. Ramadan said. “You are too Western for the Muslims, and too Muslim for the Westerners. Controversy is natural. But this particular controversy about whether I have a secret life as a terrorist or extremist is so old that, frankly, it’s – what’s the word? – boring.”p. Notre Dame aggressively scrutinized Mr. Ramadan’s résumé and body of work before hiring him, and Father Malloy, who interviewed Mr. Ramadan, said he hoped Washington would reconsider its decision to bar him.p. A spokesman for the Department of Homeland Security, Russ Knocke, declined to offer any reason for the revocation of Mr. Ramadan’s visa. Another government official, who requested anonymity because he was consulting classified information, said the revocation was based not on Mr. Ramadan’s beliefs but on “his actions.” The official would not elaborate.p. Mr. Ramadan, expressing frustration with the vagueness of such an accusation, said, “My conscience is clean, my activities are transparent and my file is empty.”p. A senior European counterterrorism official who has investigated Mr. Ramadan said European intelligence services had never turned up proof of wrongdoing on his part.p. The official added, however, that he thought the United States was wise to keep him out because of what he referred to as the professor’s “dangerous” ideas.p. Courted by U.S. Universities p. Sitting in stockinged feet before the computer in his otherwise empty home office, nibbling on Swiss chocolate, Mr. Ramadan said news of the last-minute visa revocation upset and confounded him. He has traveled to America without problems more than 30 times in the last five years, he said.p. These travels included a visit last fall to the State Department, where he delivered a lecture on European Muslims to diplomats and officials from the F.B.I. and C.I.A., he said. Mr. Ramadan has lectured Scotland Yard officers on European Muslim communities, too. Mr. Ramadan said he had received offers for a tenured faculty position not only from Notre Dame but also from an Ivy League university and, at a time when American students were hungering for greater understanding of Islam, he was courted by other top-tier schools, too.p. “A scholar like him, who’s thoroughly Islamic but has his feet firmly planted in the modern world, is – I won’t say a pearl beyond price, but certainly a pearl,” said Thomas W. Simons Jr., a former ambassador to Pakistan and author of “Islam in a Globalizing World” (Stanford University Press, 2003).p. Others sharply disagree.p. Lee Smith, who writes about Arab culture, pronounced Mr. Ramadan a “quieter and gentler” jihadist in The American Prospect last March.p. And earlier this fall, two Middle East scholars, Daniel Pipes and Fouad Ajami, portrayed the Swiss intellectual in op-ed articles as a dissembler and a wolf in sheep’s clothing.p. Several academic groups, however, from the American Association of University Professors to the American Academy of Religion, protested the government’s action as an effort to infringe on the free exchange of ideas.p. American Muslim groups questioned the government’s ability or willingness to distinguish between what they see as Muslim moderates like Mr. Ramadan and extremists.p. And the Jewish Council on Urban Affairs in Chicago expressed “deep concern” that the unexplained visa revocation was “one more horrific example of government suspicion, intimidation and exaggerated allegations against Muslims and Muslim communities.”p. Good Match Seemed Likely p. After several visits to Indiana, Mr. Ramadan accepted the offer from Notre Dame because he found there people “of faith and principle who wanted to build a space of mutual trust,” he said.p. Notre Dame, in turn, liked the fact that Mr. Ramadan is a practicing Muslim and not a detached scholar, giving him greater authority when he talks about the Koran as a “living text” open to contemporary interpretations.p. Still, several professors expressed reservations about Mr. Ramadan’s hiring because of his reputation in some corners of Europe as a militant disguised as a moderate, according to the Rev. Richard McBrien, a professor of theology.p. In his campus visits, however, Mr. Ramadan’s dynamic teaching style made a powerful impression, said R. Scott Appleby, director of the Kroc institute.p. Notre Dame was looking for a scholar who could “lead us into interreligious dialogue and intrareligious dialogue and religious-secular dialogue,” Dr. Appleby said. Mr. Ramadan’s approach "was rooted in a kind of spirituality and a scholarly method that was innovative and original and very fruitful.p. “He has developed his own philosophy, his own synthesis of the West and Islam,” Dr. Appleby continued, "drawing from Nietzsche on the one hand and Islamic philosophers on the other. He has critiques of capitalism and globalization, integrated into Islamic ideas. At the same time, he is challenging Islam to become more universalist, to embrace democracy, to help shape democracy. "p. A Troublesome Grandfather p. In 1928, Hasan al-Banna, Mr. Ramadan’s maternal grandfather, founded the Muslim Brotherhood, a revivalist movement that advocated a return to Islam as a defense against Western colonialism and decadence. In 1949, Mr. Banna was assassinated at the age of 42. Mr. Ramadan never knew his grandfather; he studied him.p. He is critical of his grandfather’s sloganeering – “The Koran is our constitution” was one motto – disagrees with him about “many things about the West,” and scoffs at the idea of an Islamic state.p. But he says his grandfather is misremembered in several ways.p. For instance, although the history of the Muslim Brotherhood is dotted with violence, and the group gave rise to more militant organizations, Mr. Banna himself was not personally violent, nor did he legitimize violence, Mr. Ramadan said. His empathy for the poor was admirable, Mr. Ramadan said, and his thinking was more nuanced than many followers and critics understand.p. Mr. Ramadan has said repeatedly that he is not affiliated with the Muslim Brotherhood, which renounced violence in the 1970’s but has been periodically banned in Egypt, as it is now. He has relatives who are members but, he said, “they are not happy with me.”p. Still, Mr. Ramadan’s genealogy is a big part of what makes him suspect to European intelligence services, just as it is what affords him a platform from which to preach about making Islam more modern.p. “People make a big issue about his lineage,” said Ingrid Mattson, a professor of Islamic studies and Muslim-Christian relations at the Hartford Seminary. "But there are millions of Muslims who will listen to him precisely because of it. That’s why it’s crazy, keeping him out. "p. In the late 1950’s, Mr. Ramadan’s father, Said, settled in Geneva after fleeing Egypt during a crackdown on the Muslim Brotherhood. Said Ramadan set up an Islamic center that became a European outpost of the Brotherhood, drawing visitors like Malcolm X.p. As a youth, Mr. Ramadan said, he was not particularly committed to Islam. He was athletic, playing soccer with a semiprofessional team, studious, and, it seemed, a born teacher.p. In 1986, at 24, he became the very young dean of a Swiss high school. That year, he also married Iman, a fair-haired Swiss woman who converted to Islam. Mr. Ramadan had known Iman since he played sports with her brother as a child.p. In the late 1980’s, Mr. Ramadan, who by then had advanced degrees in philosophy and French literature, founded the Helping Hand Cooperative, taking students to developing countries to do volunteer work and meet such humanitarian luminaries as Mother Teresa.p. His commitment to Islam grew slowly, he said, starting after the Iranian revolution in 1979, when the image of Islam began to be “tarnished” by association with fundamentalism. Years later, it hit him that he was transporting young Swiss to open their minds to other cultures while at the same time hiding his own identity. He decided to go public as a Muslim and to further his Islamic studies.p. In 1991, Mr. Ramadan spent a year and a half in Egypt studying Islamic sciences and, on his return to Switzerland, pursued a doctorate in Islamic studies and began lecturing immigrant audiences.p. When Mr. Ramadan’s father died in 1995, the Swiss government warned him that the Egyptians would arrest him if he accompanied the body home for burial, Mr. Ramadan said. He believes that it is because he provoked the Egyptian ambassador to France during a television talk show by attacking Egypt’s human rights record.p. Late that same year, France barred Mr. Ramadan. Although rumors circulated that he was kept out because of ties to an Algerian terrorist, Mr. Ramadan said he believed that it was due to pressure from the Egyptians. He challenged the ban and it was lifted, but it lingered as a stain on his reputation, which, he said, is why he finds the American ban so troubling.p. “The assumption of guilt does not get put to rest easily,” he said.p. The Proper Place of Muslims p. In 1996, while spending a year in the Britain, Mr. Ramadan started to define in writing his ideas about Western Muslim identity.p. Some Western Muslims identify themselves as a people apart, he writes in his latest book, stewing in an “unhealthy victim mentality” and an “us against them” mind-set. Instead, they should liberate themselves by developing a “rich, positive and participatory presence in the West,” which would include sending their children to public schools, getting involved in community politics and taking part in interfaith dialogues.p. In the last year, Mr. Ramadan became the de facto representative of the French Muslim community in confronting the government’s ban on Islamic head scarves in the schools.p. Recently, he appeared on a televised French debate during which he was badgered about his support for what other guests kept calling “the veil.” How could he favor forcing women to cover themselves? they asked.p. In a calm voice, Mr. Ramadan responded that he would neither force a woman to wear a head scarf nor force her to remove one. It was a human rights issue, he said, and yet once the ban became law and the choice for French Muslim girls was between going to school and wearing their head scarves, his advice was to attend school.p. Last fall, also on television, Nicolas Sarkozy, then the French interior minister, challenged Mr. Ramadan to prove he was a moderate by telling Muslim women to “take off their veils.” Mr. Ramadan refused.p. Mr. Sarkozy also challenged him to call for the abolition of the stoning of adulterous women, which is mandated by a strict reading of Islamic law. Mr. Ramadan called instead for a moratorium on stoning.p. “That way, you start a dialogue,” he said. “I won’t change any thinking in the Muslim world if I issue a blanket condemnation of stoning to please the French interior minister.”p. But Mr. Ramadan was attacked fiercely for refusing to take an absolutist stance. He was also, to his regret, lumped together with his older brother Hani, whom he calls a “literalist” Muslim. Hani Ramadan lost his job in Swiss education after publishing an essay justifying the stoning of adulterous women.p. Mr. Ramadan himself set off a storm in France last fall when he wrote an online essay criticizing several French Jewish intellectuals for being “biased toward the concerns of their community” by defending Israel – in its construction of a barrier in the West Bank, for instance – and supporting, to varying degrees, the Iraq war.p. These positions, he wrote, betrayed the intellectuals’ commitment to universal values. If Muslim intellectuals, he wrote, were expected to denounce anti-Semitism and terrorism committed in the name of Islam – which he does repeatedly, he said in an interview – why didn’t Jewish intellectuals bear a similar responsibility to condemn “the repressive policies of the state of Israel” and to oppose discrimination against Muslims in Europe, he asked.p. Bernard-Henri Lévy, a prominent European intellectual, promptly labeled Mr. Ramadan a champion of double talk and said he had written an “anti-Semitic text.” The label of anti-Semite stuck to him even though, Mr. Ramadan said, he has been decrying anti-Semitism in the Muslim world for years.p. Mr. Ramadan’s notoriety in France is now such that his publisher decided his next book will be called, “Should We Make Tariq Ramadan Shut Up?”p. The Road to Notre Dame p. After receiving an American visa last spring, Mr. Ramadan rented a spacious house near Notre Dame, shipped his family’s belongings there and enrolled his four children in school.p. Mrs. Ramadan lined up a position as a consultant to an interfaith dialogue at the Center for Women’s Intercultural Leadership at St. Mary’s College in South Bend. She was looking forward to working outside the home, and to enjoying “America’s famous openness” to cultural and religious differences, she said.p. Now they are in limbo.p. One recent evening, at about 9 p.m., Mr. Ramadan’s phone rang and he pounced on it. Finally, it was the lawyer from Notre Dame with news. The State Department, she said, had alerted the American consulate in Switzerland to schedule an appointment for Mr. Ramadan to reapply for a visa. A fair and thorough review was promised.p. “I will call first thing tomorrow,” he told his wife when he hung up. “There are no guarantees, and, she says, nothing is likely to be decided before Nov. 2. But at least we can take action.”p. Eric Lichtblau contributed reporting from Washington for this article and Don Van Natta from London. p.