The exciting stories of three spies who infiltrated Al-Qaeda for Western intelligence are worth revisiting as the 20th anniversary of 9/11 approaches. Why was the information they could have offered not used more effectively?

The popular belief, repeated many times since the 9/11 terrorist attacks, is that recruiting informers and deploying infiltrators against Al-Qaeda is extremely difficult due to its highly compartmentalized cell structure. But, in truth, British, French, and American intelligence agencies all had agents capable of infiltrating Al-inner Qaeda’s circle, including its training camps in Afghanistan, in the run-up to 9/11, according to RT News.

Omar Nasiri was raised in Belgium after being born in Morocco in the 1960s. He became involved in gun smuggling for the GIA, an Algerian Islamist organization that slaughtered tens of thousands of people during the Algerian Civil War, in the early 1990s. After getting into difficulties for stealing money from the group, he approached French intelligence, and they recruited him as a spy inside the GIA.

Nasiri continued to work as an arms dealer, supplying the weaponry used in the GIA hijacking of an Air France flight in 1994, with the goal of crashing the plane into the Eiffel Tower. When French special forces boarded the plane, the plot was foiled, but Omar continued to supply weapons to the gang. He even drove an explosives-laden automobile through France and Spain to deliver it to a GIA agent in Morocco. Gilles, his French handler, approved the plan, and when a massive car bombing occurred in Algiers a few weeks later, Gilles seemed unconcerned.

Years later, when Nasiri authored his autobiography and gave an extended interview to the BBC, these revelations came to light.

In the summer of 1995, Omar travelled to Pakistan on a fresh mission to infiltrate Al-Qaeda training camps along the Afghan-Pakistan border. He spent a year in the camps, where he learned how to use weapons and create homemade explosives as well as receiving religious indoctrination.

Nasiri returned to Europe and joined British intelligence, where he was charged with infiltrating the developing Islamist movement in London and the Al-Qaeda support network known as Al Muhajiroun. But Omar found it tedious because he wasn’t plotting attacks in the UK, and he repeatedly requested that his handlers return him to the Afghan camps. He sent British intelligence phone numbers for his Pakistani contacts and even transferred money provided by the British government, but the suits wouldn’t let him return to the training camps.

His spymasters at MI5 and MI6 refused to let Nasiri return to Afghanistan even after the Al-Qaeda bombings of two U.S. embassies in East Africa. Nasiri ended his career as a spy in 2000 after a spell working for German intelligence, which was equally difficult. Nasiri would have received advance notice of the 9/11 attacks if his handlers had taken him seriously and let him to return to Afghanistan, as we will see in the narrative of Aimen Dean.

MI6 acquired a new informant at the same time Nasiri was growing tired of his supervisors’ refusal to let him spy on persons who were preparing terrorist acts. Aimen Dean grew up in Saudi Arabia after being born in Bahrain in 1978. Following the Soviet-Afghan war, he, like Nasiri, got involved in worldwide jihad. Before joining an Islamist charity in Baku, Azerbaijan, and subsequently the Moro Islamic Liberation Front in the Philippines, he fought in Bosnia as part of the Western-backed Bosnian mujahideen. Dean went on to write a book about his life and has been interviewed extensively.

Dean’s perspective was modified after the Al-Qaeda embassy attacks in 1998; up until that point, he had been entirely dedicated to the war and had even made an oath of devotion to Osama Bin Laden. However, witnessing the misery and devastation in Kenya and Tanzania changed him, particularly after he narrowly escaped the U.S. airstrikes on the Farouq training camp in the aftermath of the embassy attacks.

Dean was apprehended by Qatari authorities not long after leaving the camp and immediately poured his guts, telling them everything he knew. They recommended that he apply for a career as a spy with Western intelligence, and after some thought, Dean chose the British. He spent the next eight years as an MI6 undercover operative.

Dean told his new handlers everything he knew about Al-Qaeda, including the organization’s leadership, bank accounts, travel routes, and funding sources. They dispatched him back to Afghanistan in 1999 to infiltrate the training camps and gather intelligence on upcoming attack preparations.

According to his book, Dean spent the following two years helping to foil the Millennium Plot, brokering an agreement with the Taliban to ensure the Sydney Olympics were not assaulted, and escaping from a Pakistani ISI cell with the help of MI6. He even claims to have met Abu Musab Al Zarqawi, a future Iraqi Al Qaeda leader.

In the summer of 2001, the camps were buzzing with rumors that something huge was about to happen, so Dean was dispatched to London with letters instructing local Al-Qaeda leaders to disperse. All of this was reported to MI6 officers, but they curiously did nothing. They didn’t send Dean back to Afghanistan to try to gather more details, nor did they pass him over to the CIA, which was desperately trying to contact friendly governments about agents inside Al-Qaeda at the time.

The 9/11 attacks occurred a few weeks later, but MI6 never put Dean back inside Al-Qaeda, preferring to employ him to entrap Muslims in bogus terror schemes. It never gave him to the CIA to aid in the search for Al-Qaeda members in Afghanistan and Pakistan, or to aid in the reconstruction of the 9/11 plot to find all the perpetrators.

The narrative of Aukai Collins, a former Islamist turned spy for the West who wrote a book about his experiences, shows a similar trend of failing to capitalize on opportunities in the run-up to 9/11. Collins had a remarkable but horrific life: his mother was murdered by gangsters when he was 16 years old, and he spent the next several years fleeing from jails after being imprisoned for street-level gang offenses.

Aukai was drawn to the burgeoning militant Islamic organization in the mid-1990s after converting to Islam in prison. After failing to join the Bosnian jihad, he spent time in training camps in Kashmir and Afghanistan, where he met Omar Saeed Sheikh, the eventual killer of Daniel Pearl.

Collins got his first taste of fighting during the Chechen war, when he traveled to Chechnya and joined the fight against Russian forces. He met and married a lovely 16-year-old girl, before a Spetsnaz attack on the camp where he was residing resulted in Aukai getting catastrophic damage to his leg, which had to be amputated.

Aukai got disillusioned after more escapades with Chechen mafiosos, and the Al Gama’at al Islamiyya attack in Cairo in April 1996 convinced him of the threat posed by Islamist extremists. Collins entered the U.S. embassy in Baku and informed a CIA officer of what he knew and had done, offering his services as a spy. The CIA told him it couldn’t employ him, but didn’t explain why, and instead paid for him to return to the United States and join the FBI.

Collins operated as a counter-terrorism informant for the FBI for the next four years, largely for the FBI but also on joint FBI-CIA operations. One plan envisioned establishing a terrorism training camp in the United States in order to spy on and follow everybody who attended, but it was scrapped after then-Attorney General Janet Reno called it off.

While on a CIA mission to infiltrate the Islamist community in London in early 1998, Aukai received a startling offer: Bin Laden personally wanted him to travel to Afghanistan and speak with him. While the FBI was in favor of entering the camps, his CIA handler, Tracy, put a halt to the plan, saying, “There was no way the U.S. would approve an American operative going undercover into Bin Laden’s camps.”

This is strange because the CIA’s Bin Laden unit, Alec Station, has been seeking to track down someone close to Bin Laden for years. Moreover, in the prologue to Nasiri’s book, Michael Scheuer, the CIA officer who built Alec Station, claimed that Omar was exactly the type of spy the CIA lacked. So why was Aukai assured that it would “never, ever happen” despite a personal invitation from Bin Laden?

Collins left the CIA after this setback, spending time in Albania during the Kosovo conflict before returning to America and rejoining the FBI. He alerted the government about Hani Hanjour, the hijacker pilot of the plane that crashed into the Pentagon on 9/11, after meeting him in Phoenix and learning that he was taking flight training, but the feds never followed up.

His relationship with the FBI worsened after his handler was promoted and replaced by a man who didn’t trust Aukai, and he resigned. After witnessing the 9/11 attacks on television, he contacted the FBI and offered his assistance, even suggesting that he travel to Afghanistan to track down Al-Qaeda members. Instead of taking him up on his offer, the FBI put him through a polygraph test and accused him of knowing about the attacks.

What were the FBI, CIA, MI5 and MI6 up to, exactly? Before and after the 9/11 attacks, they consistently failed to leverage their human assets within Al-Qaeda. For example, when Aimen Dean reported in early summer 2001 that a major Al-Qaeda strike was impending, Western intelligence might have dispatched him, Nasiri, or Collins (or all three) to Afghanistan to investigate further, but they didn’t.

It’s unclear if these stories are about sadly squandered chances, egregious institutional incompetence, or something more sinister. But, unfortunately, while Dean is a well-known character, Nasiri is less well-known, and Collins died in 2016. So the complete story of the spies inside Al-Qaeda may never be revealed.