This is a sentence that will probably find its way into every history book: "It turns out that we were all wrong." This assessment, reached by former US chief weapons inspector David Kay, has been causing significant problems for US President George W. Bush for months. The inflated story about Saddam's alleged arsenal of horror could be one of the factors that may cost him his reelection.

Another remark Kay made during his testimony before a congressional panel in January has not yet become as widely known: "The Germans and their intelligence services believed that there were weapons of mass destruction in Iraq."

Does this mean that key reasons to go to war were supplied by Germany, an opponent of the war? Both the German government and the Federal Intelligence Service, or Bundesnachrichtendienst (BND), have been worried about a backlash from Washington for months. On the weekend before last, their fears became reality. Through an article printed in the Los Angeles Times, the US government leaked the information that Berlin allegedly bears a portion of the responsibility for the debacle in Iraq. According to the article, this is because the Germans are principally responsible for the fantastic story of biological weapons laboratories being hidden in mobile containers that the dictator supposedly had driven back and forth across the country in trucks. It was precisely this laboratory for toxic substances that US Secretary of State Colin Powell used as one of his central arguments in attempting to convince the UN Security Council of the dangers posed by Iraq.

The erstwhile key informer in the case is now suspected of being nothing but a con man. According to Kay, the BND was deceived by a "total liar," one of the agitators that the shady Ahmed Chalabi's Iraqi National Congress (INC) dispatched to the intelligence services to exaggerate the threat posed by Saddam Hussein. In Washington today, the fact that the intelligence services relied on Chalabi's agents is viewed as one of the main reasons behind this intelligence fiasco. Agent "Curveball," as the BND source is called in the US files, is apparently the brother of one of Chalabi's closest associates.

Exactly how much "made in Germany" was part of the American justification for going to war, which is increasingly proving to have been nothing but hot air? Is it possible that Germany's red-green coalition, itself so critical of the war, unintentionally bears some responsibility for the escalation? As a result of the revelations about "Curveball," the debate on just how reliable the information supplied by intelligence services is has now washed over to Germany.

The intelligence services have never been as influential as they are today. Nowadays, war and peace depend on the reliability of a sector that traditionally prefers to keep its operations far from the public eye. For this reason, its credibility has now come under greater scrutiny.

Until now, the BND was in a relatively strong position as far as Iraq was concerned. The agency had consistently dismissed the horrific reports of Saddam's renewed efforts to build nuclear weapons and his supposed alliance with Al Qaeda as nonsense.

But now the agency, and with it the administration, is coming under increased pressure: "Either the BND wasn't doing a very good job, or the government passed on the information provided by the BND in a manner that was simply negligent. In either case, the government bears full political responsibility," says the foreign policy spokesman of the CDU and CSU coalition, Friedbert Pflüger.

As a result, the Schröder administration now finds itself accused of having misled Germany's lower house of parliament, the Bundestag. BND Director August Hanning has testified in a closed session before the members of the foreign policy committee on two occasions – on November 13, 2002 and February 12, 2003. In both sessions, the panel was interested in Iraq's weapons of mass destruction, and the alleged mobile weapons laboratories played a central role in both cases.

The question that now arises is this: How precise was the BND in informing the delegates about its reservations? Did it explain that all of its information was based on statements made by a single source?

Pflüger feels deceived by the concealment of this detail, but also by the fact that the informant's connection to Chalabi was not mentioned. "It would have been absolutely necessary to at least tell us that there was only one source, and one of dubious value at that." It's an accusation that the administration refuses to accept, claiming that it only became aware of these close connections to the exiled opposition party after the war.

The case will have parliamentary repercussions: Pflüger is demanding that the taped recordings of the foreign policy committee's sessions be made public, so that it can be determined whether the federal government misled parliament. This is certainly a delicate demand. Portions of the minutes, the opposition party claims, are missing for inexplicable reasons. The recording allegedly ends with one of the questions about biological weapons, and only resumes after the BND's response.

Agent "Curveball" has long been viewed as one of the BND's most important trump cards. In 1998, the young chemist arrived in Germany seeking political asylum, and quickly came into contact with the intelligence service.

At first, the experts refused to believe the story they were being told. The informant claimed that, as a student at the top of his class at the University of Baghdad, he was recruited by the regime to work on a special project. He claimed that, as an engineer, he was asked to participate in the development of the mobile laboratories. During meetings with the BND, the man kept revealing new details and had agency staff draw detailed plans of the weapons labs. The containers, he claimed, were kept hidden under the eaves of grain silos. He said that three had been completed by the time he left the country.

After months of questioning, the story was finally classified as being technically plausible and "credible." The man was also considered authentic. After all, a con man couldn't possibly have survived such a marathon of questioning without eventually contradicting himself.

The BND notified the chancellor's office, and select members of parliament were also briefed on this supposedly alarming information. Although there was no talk of war at the time, the BND believed that the biological weapons laboratories proved that Saddam was still in violation of UN sanctions. In 2001, the Americans and the British were also brought into the loop. The BND wanted to know whether anyone else had heard anything about the trailers. No one had. At first, as the invasion was becoming increasingly likely, the agency's report became political material. The CIA, itself heavily under pressure from the Bush administration, urged the German government to release "Curveball's" stories for Powell's appearance before the UN. Many a politician in Berlin would have preferred to lock the story away in a safe, but the CIA, at its headquarters in Langley, was already quite familiar with the details of the report.

Berlin eventually agreed, albeit reluctantly. However, the Germans also demanded that it be disclosed that the story was based on a single source and had not yet been corroborated, and that there was no information on what had transpired since 1998, when the Iraqi defected. And, because "Curveball's" family was still in Iraq, Powell was not to reveal his identity under any circumstances.

Of course, the showdown in New York took an entirely different course. As a precaution, Foreign Minister Joschka Fischer took along a BND expert when he attended the session of the Security Council on February 5, 2003, and the expert was seated no more than six feet away from Powell. However, the US Secretary of State not only used the German "eye witness" (Powell) to support his argument, but claimed that three other informants had also reported on the laboratories. One of them was a major who had defected, a man even the US intelligence services believed had apparently been "briefed" by Chalabi's INC. Until then, the BND had not been told anything about the major or the other sources.

The three slides presented by Powell, which were quickly broadcast around the world, were identical to the drawings that had been prepared at the BND on the basis of information provided by "Curveball." At the time, some of the intelligence agents who were watching Powell's dramatic presentation on a large screen in Berlin were even proud of themselves: "That came from us."

Others began to feel queasy. Powell's statements had not just demonstrated that the Americans had ignored Germany's restrictions on the use of the information. They had also omitted all the details that could or should have substantiated the allegations. For former weapons inspector Kay, this was the central mistake: "If Powell had said that we have only one source to support our claims, a source we have never met and whose name we don't even know, he would have been ridiculed."

Officially, however, the BND kept a low profile, even when, after the fall of Baghdad, there was still no evidence of Saddam's arsenal. After all, a few suspicious-looking trailers had been found and Bush, without further ado, had even declared that this was proof that all the allegations were true. The BND experts were certainly suspicious when they saw that the trailers did not resemble those portrayed in "Curveball's" drawings. But, when questioned on the matter, the BND responded that it did recognize "elements" of its old sketches. Perhaps the new trailers were simply an updated version, the German agency conjectured.