Mohamedou Ould Slahi—al-Qaeda relationship

Mohamedou Ould Slahi’s relationship with al-Qaeda was real, but its meaning changed over time and became the subject of a dispute that followed him into years of detention. He joined during the anti-communist war in Afghanistan, then said he withdrew when the conflict shifted to fighting among Muslim factions. Later contacts with people who remained connected to the organization—including relatives and acquaintances—were treated by the United States government as evidence that the relationship had continued. The book’s account turns on the gap between those intermittent connections and the government’s broader conclusion that Slahi was still part of al-Qaeda when captured.

Joining during the Afghan war

In Germany, where he had gone to study electrical engineering, Slahi interrupted his education to join the insurgency against Afghanistan’s communist-led government. In early 1991 he spent seven weeks at a training camp near Khost, received instruction in light arms and mortars, and swore an oath of loyalty to al-Qaeda, the camp’s operators. The book situates this decision in a period when young men traveled openly to join the anti-communist cause, which the United States and Western countries actively supported. The oath was consequential, but it belonged to a particular political and military setting; the account does not present it as proof that Slahi shared every later aim of the organization.

After returning to his studies, Slahi went back to Afghanistan in early 1992, when the communist government was nearing collapse. He joined a unit commanded by Jalaluddin Haqqani during the siege of Gardez, which fell three weeks after his arrival. Once the communist government fell, however, rival Mujahideen factions began fighting one another for power. Slahi later explained that he did not want to fight fellow Muslims and saw no reason to take part in a struggle over who would become president or vice-president. He described his purpose as opposition to the communist forces that had prevented Muslims from practicing their religion. The change in the war’s character, in his account, marked the end of his commitment to al-Qaeda.

Withdrawal and continuing connections

Slahi maintained that his departure preceded al-Qaeda’s mid-1990s interest in jihad against the United States. He acknowledged that he had fought with al-Qaeda, but distinguished that earlier alliance against communism from the organization’s later direction. He said he did not join that project and regarded himself as independent of the conflict between al-Qaeda and the United States. This was his account of the break, not a claim that all his links to former companions immediately disappeared.

Back in Germany, Slahi completed his electrical-engineering degree at the University of Duisburg and lived and worked there through much of the 1990s. He remained friends with, or in contact with, companions from Afghanistan, some of whom retained al-Qaeda ties. He also had a direct family connection to Mahfouz Ould al-Walid, known as Abu Hafs al-Mauritani, an al-Qaeda Shura Council member and senior theological adviser to Osama bin Laden. Abu Hafs was Slahi’s distant cousin and brother-in-law. They were in occasional telephone contact, and Slahi twice helped him transfer $4,000 to his family in Mauritania around Ramadan. These details made the relationship more complicated than either complete separation or continuous operational involvement: Slahi’s personal and family ties persisted, while he maintained that he had left the organization’s cause.

Suspicion and detention

When Slahi returned to Mauritania in January 2000 after twelve years abroad, he was detained first by Senegalese police and then by Mauritanian authorities at the behest of the United States. Federal Bureau of Investigation agents questioned him about the Millennium Plot, a suspected plan to bomb Los Angeles International Airport. Authorities concluded that there was no basis to believe he had participated and released him on February 19. In September 2001, Mauritanian authorities detained him again for two weeks, and Federal Bureau of Investigation agents again asked about the plot; he was released, with Mauritanian authorities publicly affirming his innocence.

On November 20, Slahi went voluntarily with Mauritanian police for further questioning. Eight days later, a Central Intelligence Agency rendition plane transported him to a prison in Amman, where Jordanian intelligence services interrogated him for seven and a half months. His account to a later review board was that the Jordanian questioning focused especially on the Millennium Plot. The book notes that the available record does not show that the Central Intelligence Agency supplied Guantanamo prosecutors with intelligence from the Amman interrogation. A CIA inspector general report also described the agency’s interest in keeping isolated detainees who might disclose how they had been held; the passage offers context for secret detention, not proof of what Slahi said or what investigators established about al-Qaeda.

A further link entered the case after the capture of Ramzi bin al-Shibh in September 2002. Slahi said bin al-Shibh identified him as a man he had met in Germany in 1999 and who had hosted him for a night. According to Slahi’s account of the interrogation, bin al-Shibh also said that Slahi had advised him to travel to Afghanistan for training, and speculated that Slahi was an operative of Osama bin Laden. The connection was therefore more specific than a distant association: Slahi had met and hosted bin al-Shibh. But the claims about what that meeting meant came through an interrogation and a later account of it, and did not by themselves establish that Slahi had remained an al-Qaeda member or participated in the September 11 attacks.

Detention and the legal dispute

Slahi arrived at Guantanamo on August 5, 2002, with thirty-four other prisoners. The book states that there is no indication he was then regarded as an especially high-value detainee. His detention unfolded amid a wider change in interrogation policy: the military developed special interrogation plans, despite objections from Federal Bureau of Investigation and Criminal Investigation Task Force agents. In 2003–2004, Slahi himself was subjected to a special interrogation plan approved by Defense Secretary Donald Rumsfeld. The relationship at issue had thus become more than a historical question: allegations about Slahi’s connections were pursued within a system that used coercive methods, while the account distinguishes those methods from reliable proof of continuing membership.

When the government opposed his habeas petition, it did not argue that Slahi was a major al-Qaeda figure or that he had planned attacks. Its position, as summarized by the appeals court, rested on his oath, his associations, and assistance that included hosting leaders and referring aspiring jihadists to a known operative. Judge James Robertson considered the question under the then-applicable test of whether Slahi was an active member when detained. The judge concluded that the sporadic contacts offered by the government did not establish that he remained part of the organization. Some interactions might have been gestures of support, but, in the court’s assessment, they did not amount to criminal material support for terrorism; their limited frequency also fit Slahi’s account that he was trying to avoid close relations with al-Qaeda members without making himself their enemy.

Judge Robertson granted the habeas petition and ordered Slahi’s release. The United States Court of Appeals for the D.C. Circuit later reversed and remanded the case after adopting a broader standard for deciding whether a detainee was part of al-Qaeda. Under that standard, contacts with active members could remain relevant even if they did not independently prove membership at the time of capture. The appeals court also emphasized that the government had not criminally indicted Slahi for material support, nor sought to detain him on the ground that he aided the September 11 attacks. The outcome therefore left the central question unresolved: whether an oath taken in 1991 and intermittent relationships afterward demonstrated continuing membership a decade later.

Meaning of the relationship

The book presents Slahi’s history with al-Qaeda through distinct stages: participation in an anti-communist struggle, withdrawal when the war became factional, and continued but sporadic personal connections with people who remained involved. The government’s case drew those stages into a single argument about membership at the time of detention. His own account insisted on the difference between past affiliation and present allegiance; the courts’ changing standards determined how much weight could be assigned to the intervening relationships.

That distinction mattered beyond Slahi’s individual case. Early questioning and detention focused on the Millennium Plot, while the later appearance of bin al-Shibh’s account connected Slahi to the September 11 investigation. Yet the government eventually abandoned its claim that Slahi was detainable because he had aided the attacks, acknowledging that he probably did not even know about them. The relationship remained consequential, but the record described in the book does not collapse association, assistance, past membership, and participation in an attack into one fact. Instead, it shows how a genuine history of affiliation and contact could be made to bear a much larger legal and political burden than the underlying evidence clearly resolved.