"In our constitution religious communities are not subject to state surveillance, nor are they being registered as such. It is not the role of the state to scrutinise spiritual practices."
This remark, in the preamble to a 93-page document, came from the German government three years ago in response to questions raised by parliamentarians keen to know more about the country's 3.2m Muslims.
Almost a year later, in 2001, Germans were shocked when it emerged that three of the four hijack pilots behind the September 11 attacks in the US - and one of the suspected masterminds - had been Hamburg residents.
A community that had been left to its own devices has since become an object of unprecedented scrutiny. It is a political U-turn that is building a wall of distrust between Muslims and non-Muslims and, some say, could end up fuelling extremism.
"We are being observed, we are being harassed. The general sentiment for many loyal citizens is one of increasing discomfort," says Nadeem Elyas, chairman of the Central Council of Muslims in Germany (ZMD), the most politically active of the four large federations of Muslims in the country.
For Cornelie Sonntag-Wolgast, the Social Democratic chairman of the interior committee in parliament, the feeling of estrangement is reciprocal. "A lot of efforts went into the Muslim- Christian dialogue right after September 11. But we have grown disillusioned. I would like to see clearer gestures coming from our Muslim partners."
Of Germany's main religions, Islam is the most recent import. Judaism appeared with the Romans, followed by Christianity's gradual extension up to the 9th century, but there were only a few thousand Muslims by the end of the second world war.
Since 1961, however, when the first Turkish "guest workers" arrived to help power the country's economic renaissance, Islam has become Germany's third largest denomination after Protestantism and Catholicism - a development that, until two years ago, had drawn little interest.
In a paper written just before the September 11 attacks, Ursula Spuler-Stegemann, author of Muslims in Germany - side by side or together?, warned: "In the past few years, almost unnoticed, a self-sufficient Muslim parallel society has developed in nearly all areas of life." The attacks shook Germany, she says, and justified more aggressive interference in the affairs of minorities - something the constitution and Germany's postwar trauma had previously prevented.
"It has become much easier to go after extremists without being branded a xenophobe," she says. "There is a realisation that by refusing to act you do a disservice to the silent majority of liberal Muslims."
Two bills adopted in the past two years have boosted security. They include the legalisation of profiling and the capacity to shut religious organisations. Since their enactment, the ZMD claims 80 mosques and 400 offices and apartments have been searched. According to the interior ministry, three nationwide organisations were banned between December 2001 and January this year.
"The state has a duty to look after security," says Dr Elyas, who was born in Mecca in 1945 and has lived in Germany since 1964. "But it must be done in a way that does not push the large majority of law-abiding Muslims on to the other side."
Most conflicts involving the Muslim community are still resolved by Germany's consensual approach. The King Fahd Academy, a school financed by Saudi Arabia, was allowed to continue operating last week despite evidence that inflammatory preaching had taken place there. The school will have to have its syllabus approved and ban fundamentalists from its teaching staff.
Last month work resumed on what should become Berlin's largest mosque, on a site belonging to Turkey. The striking Ottoman-style building was almost 10m higher than allowed by local planners. Rather than being destroyed, the mosque paid a fine. .
The current debate about Muslim headscarves in state schools could prove harder to defuse, however, especially since the German state - while guaranteeing religious freedom - entertains close relationships with the dominant Christian churches, on whose behalf it collects taxes.
The constitutional court ruled in September that while the state of Baden-Württemberg had no grounds to ban Fereshta Ludin, an Afghan-born teacher, from wearing a headscarf in school, it was free to enact legislation to this effect.
Five states have since said they will legislate to ban Islamic headscarves while continuing to allow yarmulkes (skull caps), crucifixes and habits.
"For many people the scarf is an expression of fundamentalist principles. The yarmulke is not," says Karl Feller, deputy Bavarian minister for religious affairs. "And. . . the Bavarian constitution says state schools should reflect Christian principles."
Critics say the bills will probably be struck down by the constitutional court for being discriminatory. Advocates note that secular Turkey, where two-thirds of Germany's Muslims have their roots, bans headscarves from universities, schools and the civil service.
"But we live in Germany. Let us not discuss what the headscarf means in Turkey or in Afghanistan. It is irrelevant," says Dr Elyas.
"What Bavaria is contemplating I call a provo-cation."