SIMON MARKS: Thousands of miles away from the hustle and bustle of New York and Washington, the attacks on the World Trade Center and the Pentagon have had a profound effect on the German city of Hamburg.
This northern port has found itself at the center of the international investigation into the al-Qaida figures responsible for the attacks, because three of the nineteen Sept. 11 hijackers lived here, along with at least four senior bin Laden lieutenants, who were accused of arranging finance for the attacks and providing logistical support for them.
Walter Wellinghausen is Hamburg's state secretary, one of the city's top officials.
WALTER WELLINGHAUSEN, State Secretary of Hamburg: It was quite a surprise because when you look in the files today, you don't find even a letter about this situation in Hamburg. Our security officers, our police, our intelligence service, didn't have any information about this group in Hamburg.
SIMON MARKS: No information until the early hours of Sept. 12, 2001, when a tip from a journalist led police to Marian Strasser 54, an anonymous apartment in a quiet residential area in the south of the city. It was rented in 1992, by Sept. 11 hijacker Mohamed Atta.
For eight years, Atta was enrolled as a student of architecture at the city's technical university nearby. He's remembered by staff as a dedicated and talented student, whose thesis on urban renewal in Syria won him high marks.
But by night, investigators say, Atta was plotting with two friends: Marwan al-Shehhi and Ziad Samir Jarrah, who would also participate in the deadly hijack mission. All three died on three of the planes used in the Sept. 11 attacks.
Investigators say Mohamed Atta and his colleagues were completely hidden within Hamburg's Muslim community. They had done nothing to draw attention to themselves, and in this city, which is easily accessible from most cities in Europe and boasts a generally liberal social atmosphere in which virtually anything goes, it wasn't difficult to hide out.
JOSEF JOFFE, Editor/Publisher, Die Zeit: So if I were a terrorist and I was looking for a staging ground in Europe, I would probably go to Germany for the simple reason that this is the most liberal polity on the continent.
SIMON MARKS: Josef Joffe is the editor and publisher of the Hamburg-based weekly newspaper Die Zeit.
JOSEF JOFFE: First of all, we have a university system which requires no tuition, so you can stay forever. Secondly, we have a university that doesn't kick you out because you don't do any work. You can just go on forever and ever.
So it's a good place to be a student in Germany if you want to hang out and stay without major, or even minor, perturbation by the authorities.
And finally, I would say Germany is probably the most liberal country on the continent.
SIMON MARKS: Which is precisely why Germany, in general, and Hamburg, in particular, have proved so attractive to Muslims from all over the world.
Hamburg's 130,000 Muslims constitute nearly 8 percent of the city's population, more than twice the national average. Their leaders speak approvingly of the country's liberal ethos that has allowed many community members to escape more restrictive societies elsewhere.
MUSTAFA YOLDAS, President, Islamic Council of Hamburg: I was coming from Turkey, and I cannot speak as free as I am doing now with you in that country.
SIMON MARKS: Mustafa Yoldas has lived in Germany for 36 years, and heads the city's Islamic council. He insists that the hijackers intentions were as hidden from their fellow Muslims, as they were from everyone else.
MUSTAFA YOLDAS: What Mohamed Atta and his friends did, they separated; they were not very active Muslims in the community.
You must believe me that people of bad intentions, or terrorists, would not come to a mosque like this, in which 3,000 people every day are coming and praying and eating and buying something, that terrorists go to the council and say, "Hello, listen to me, I have a plan and I want to make this action."
It is not probable that terrorists go into the mosque and spread their plan.
SIMON MARKS: There are 44 separate mosques in Hamburg today, and the one Mohamed Atta visited most regularly can be found in some rooms above a fitness center.
The al-Quds mosque has been a focus of police investigation ever since the attacks. Its founder and president, Aziz el Alaoui Sossey, says that no one at the mosque had any involvement in Mohamed Atta's plans.
AZIZ EL ALAOUI SOSSEY: (Translated): I cannot say who is good or bad. It's not written on their forehead.
It's exactly the same at church. You sit in the first row and the priest is opposite to you and he cannot know if you are a murderer or not. It is the same here.
SIMON MARKS: Aziz El Alaoui Sossey doesn't give many interviews these days. He says he's disappointed that the German media has depicted his mosque as a supportive center where terrorists could secretly hatch their plots; a claim that he says has led to lower attendances that are jeopardizing the mosque's future.
AZIZ EL ALAOUI SOSSEY: (Translated:) The community is affected very much, and it's not their fault. And all the people who pray here, it's not their fault either.
And we are very sorry about what's happening everywhere because Islam is a religion of peace, and you do not kill innocent people. It's claimed that we helped them financially, that we helped them commit these acts, but now we cannot even pay our own rent.
SIMON MARKS: Hamburg's entire Muslim community has come under an investigative microscope since the city's links to Sept. 11 became known.
That's caused tensions between the city's Muslims, who accuse police of racial profiling, and Hamburg's security agencies, who say they still have much more work to accomplish unraveling the city's al-Qaida cell.
A series of high-profile arrests has already been made, and one alleged paymaster for al-Qaida, a 28-year-old Moroccan, Mounir El Motassadeq, went on trial this week here, charged with more than 3,000 counts of accessory to murder.
The trial taking place in the city's courts of justice is the first anywhere in the world directly linked to the events of Sept. 11 to move beyond a preliminary phase.
Manfred Murck heads the Office for Constitutional Security in Hamburg, an agency that focuses on undercover work here.
MANFRED MURCK, Office for Constitutional Security: Within the more than 100,000 Muslims living in Hamburg as normal people, having their life here as good people, we think there are about, let's say, 1,500 who have more on their mind, who are in sympathy to an interpretation of the Islam, which is more radical.
And within that we think we have a group about 100, who are militant Muslims and who are a real danger for us and for others.
We have to communicate this and we have to ask the others, the good guys, if I can say so, to help us to find out who are the bad guys.
SIMON MARKS: But as they go about that work in Hamburg, officials now say they're encountering a problem identifying "the bad guys" from a completely unexpected quarter.
At a time when U.S. intelligence agencies are warning that al-Qaida has regrouped and is threatening to launch a fresh wave of attacks against U.S. interests, both at home and overseas, the authorities here in Hamburg say their investigations into the activities of al-Qaida supporters have run into a problem.
SIMON MARKS: They say they're not getting the cooperation they need from the authorities in the U.S.A., and they're worried that a political dispute between Washington and Berlin is hampering their ability to protect the public.
It's been four months now since President Bush and the German Chancellor Gerhardt Schroeder, once warm allies, have spoken to one another, after the German leader infuriated the White House by ruling out support for U.S. military action against Iraq.
In Hamburg, the police say that breakdown in communications between the U.S. and German governments has also led to a dramatic reduction in the amount of investigative help they're getting from the U.S.A.
Bobo Franz is Hamburg's top police officer, and he's speaking out after one recent investigation into a cell suspected of planning an attack on the Japanese embassy in Berlin had to be abandoned.
BOBO FRANZ, Hamburg Police: I am quite sure that there is more information, but they didn't give us that information. And that is a problem for us because we have not been able to act, to handle this case without having information.
SIMON MARKS: Is that frustrating?
BOBO FRANZ: Yes, in a special way it's frustrating, because in my opinion it is not the way which we can go when we want to fight against international terrorism.
SIMON MARKS: The situation is so bad, that last week Hamburg's state secretary, Walter Wellinghausen, traveled quietly to Washington for direct talks with officials at the CIA and the FBI.
His aim? To try urgently to bypass the blocked communications between the U.S. and German federal authorities.
WALTER WELLINGHAUSEN: We would like to establish a direct connection between the American security department, like the CIA and the FBI, directly linked to the Hamburg department of security police or intelligence service; not the typical way we normally have through the federal government, but "direct on the talking level," we call it.
SIMON MARKS: At the U.S. Embassy in Berlin, which, like many missions overseas, is now blocked off from public access because of the global terrorist threat, a spokesman declined to comment on the claims leveled by the police in Hamburg.
In response to NewsHour inquiries, the U.S. Justice Department and FBI in Washington also said they would not comment on their relations with German law enforcement.
The Hamburg authorities say even success in existing prosecutions is now threatened by the information breakdown, and they're worried about the prospects for bringing additional defendants before the courts. In a city where al-Qaida was able to act with complete impunity before the attacks of Sept. 11, they say urgent action is needed to advance their investigations into the organization's ongoing activities here.
SIMON MARKS: So your suspicion is that your work here is not over on this matter.
BOBO FRANZ: It's not my suspicion. I'm sure that our work is not over.
We are sure that concerning this phenomenon of Islamic fundamentalism, we have to work for several years; I think the next five or ten years we will have some problem with that phenomenon.
SIMON MARKS: Since Sept. 11, Hamburg has found itself seeking to preserve the city's traditional liberties, while taking stronger measures to keep terror groups from operating here. It's a tough balance to strike. The authorities say their chance to neuter al-Qaida's operations is unnecessarily being made even harder.