Dublin, Republic of Ireland (CNN) -- In hindsight, Aicha el-Wafi can see that the warning signs about her son Zacarias Moussaoui were present as he was growing up in southern France.
"If I had known he would end up with this group of wrongdoers, I would have attracted his attention ... but I did not see it coming," said el-Wafi. Her son remains the only man convicted in the U.S. over the 9/11 plot. "I think that when a child comes home, shrugs his shoulders and does not listen to the parents ... and says ... you are not good Muslims, there is a danger."
El-Wafi, who was born in Morocco, believes Moussaoui was victimized because of the color of his skin. "He loved a girl he was forbidden from seeing... well the Islamists and the extremists found a grievance in the heart of my son. My son was born in France, my son loves France ... but he was not accepted. He was rejected by French society.
"My son suffered a lot from daily racism," she said. In the city of Narbonne he was called a "dirty Arab and dirty negro" and told to go home. "These are words that kill a child when he is 16, 18, 19 years of age."
El-Wafi now berates herself for failing to realize that her son had become involved with radical Islamists until it was too late. But by then he had been arrested and charged in connection with the September 11, 2001 attacks on the United States. The media dubbed him the "20th hijacker."
Moussaoui was convicted of criminal conspiracy and, after making several anti-Western outbursts, jailed for life. El-Wafi accepts that her son, whom she loves "more than before," was involved with extremists, but says she believes he had nothing to do with 9/11.
Now el-Wafi is drawing on her experience by visiting schools to educate young people and parents about radicalization, and issues such as arranged marriages. In an emotional interview she described how her life was haunted by the fate of her son and images of the attacks.
El-Wafi, who spoke to CNN at a recent conference in Dublin organized by Google to tackle extremism and promote reconciliation, urged parents to be alert. "They must keep their eyes and ears open, because I was a bit naïve. I loved my children.
"Everything was fine at home after their father left: we were not living in poverty. I was working; we lived well."
She now works as an activist with French feminist group Ni Putes Ni Soumise (Neither Whores Nor Submissives) that works with Muslim families. "I visit schools, I talk to young girls with regards to arranged marriages at 14 or 15 years of age. I see the parents and tell them you must talk about your problems you have at home, you must talk about it.
"When their parents do not have a worthwhile career, education, or qualifications, the children look upon their parents as having less than nothing."
El-Wafi was 14 when she married Omar Moussaoui in Morocco. Five years later they moved to the southern French city of Narbonne where Zacarias was born in 1968. Omar regularly battered his wife until she left him in 1972, according to Jan Vogelsang, a clinical social worker who gave evidence during Moussaoui's trial. CNN could not independently verify the claim made in court and the father has not responded to the allegation.
Zacarias studied business in Montpellier before moving to London in 1993 where he took a master's degree at London's South Bank University. While living in London, Moussaoui attended the same Brixton mosque as shoe bomber Richard Reid.
Throughout the late 1990s, as Moussaoui drifted between London and elsewhere, friends at the Brixton Mosque and in France say they saw a real change in him.
Moussaoui grew a beard, started to dress in traditional Pakistani clothes and began espousing his brand of militant Islam to others. Moussaoui started to attend London's more radical mosques and was asked to leave the moderate Brixton mosque because of his talks about a jihad, or holy war, against the West.
During his seven years in London, Moussaoui's family and French investigators say he traveled to Pakistan, Afghanistan and Chechnya. In February 2001 he went to Oklahoma for flying lessons. In early August of that year, German investigators say, Moussaoui was wired thousands of dollars from Germany to Minnesota, where he began a flight-training course later that month.
His instructor at an Oklahoma flight school later testified that Moussaoui's skills were "below average." He couldn't keep a plane level, make turns or keep it on course up to FAA standards, Instructor Shahoaib Kassam said.
The money supposedly was wired from the same cell that helped suspected hijacking leader Mohammed Atta -- the most direct link investigators had to the September 11 attacks.
Moussaoui was arrested in the U.S. three weeks before the September 11 attacks on immigration charges when the Minnesota flying school reported that he had been acting suspiciously.
He was indicted in December 2001, accused of being part of a broader terror conspiracy in the months leading up to 9/11. During his subsequent trial, Moussaoui testified that he and Reid were supposed to pilot a fifth airliner into the White House.
An unrepentant Moussaoui told a stunned courtroom he rejoiced at seeing the smoldering rubble of the World Trade Center in New York and pleaded guilty to six criminal conspiracy charges.
Government sources told CNN at the time that three top al Qaeda detainees told their interrogators that Moussaoui was not meant for the 9/11 plot, but for a later terror operation. Moussaoui had said as much in open court, admitting allegiance to al Qaeda leader Osama bin Laden, but denying he was to have been part of the 9/11 hijacking of planes.
Prosecutors had questioned the validity of some of his claims.
After Moussaoui was convicted of the conspiracy charges, he faced the death penalty although some experts cast doubt on both his guilt and state of mind. Defense lawyer Edward MacMahon said he believed his client yearned for martyrdom.
Urging jurors not to sentence Moussaoui to death, MacMahon said: "The only way he can achieve that dream and then live on as some smiling face on a recruiting poster for Osama bin Laden is by your verdict. Please don't make him a hero, ladies and gentlemen. He just doesn't deserve it."
Psychiatrist Michael First also told jurors Moussaoui suffered from paranoid and grandiose delusions and disorganized thinking. Moussaoui's most persistent grandiose belief, First said, was that then U.S. President George W. Bush would free him from jail, perhaps as part of a prisoner exchange with al Qaeda.
Both of Moussaoui's sisters, who live in France, have schizophrenia and take drugs to control their symptoms while their father has bipolar disorder, according to Jan Vogelsang.
"All three have had hospitalizations," Vogelsang testified during the trial. "All have been described as delusional."
Moussaoui's father lived in a psychiatric hospital in France "too sedated to be interviewed," Vogelsang said. Nadia "believes that she turns to stone and is unable to move," she said adding that Jamilla had tried to set her mother's house on fire. Again CNN could not independently verify these statements.
In May 2006 jurors sentenced Moussaoui to life in prison. He is serving his sentence at the "supermax" correctional facility in Colorado. Although Moussaoui later claimed he lied on the stand, he screamed at jurors as he left court after sentencing: "You'll never get my blood. God curse you all."
Meetings with relatives
El-Wafi is convinced such outbursts were her son's undoing. "He was convicted of what he said in the trial -- 'death to the Jews, death to the Americans' -- but there was nothing else to hold him to. He was convicted unfairly but if he had money he'd have been able to defend himself better."
Since the trial el-Wafi, 64, has written to her son but received no response. "I told him that I love him, that I think of him, that half of me is buried with him. And even if he does not answer me, I still love him.
"And since the end of the trial, there are no more lawyers, there is no one. I do not know what has happened to my son. I asked the prison if my son did not want to have any more dealings with his mother ... I have not had a reply."
Before the trial el-Wafi said her son told her: "Mum, they want my head; there is no need for you to cry. Mum, if you love me, you must look after yourself."
Tearfully, she explained how thoughts of the 2001 attacks and her son haunted her. "It is just too much of a price to pay, believe me, because my life since September 11 is hell. I really would like to forget it for a few hours. He prevents me from sleeping; he is still in my thoughts."
In the wake of 9/11, el-Wafi, who still lives in Narbonne, approached victims' relatives to request a meeting. She said she wanted to "show them that I am not in agreement with what happened. I share their pain."
One of those she met in the U.S. in November 2002 was New Yorker Phyllis Rodriguez, who lost her 31-year-old son Greg in the World Trade Center and was speaking out against the war in Afghanistan as well as the draconian USA Patriot Act. The two women formed a bond and began to work with the Forgiveness Project, among other organizations, in a bid to promote reconciliation.
In December 2010 Rodriguez described that meeting at a TED conference, organized by the non-profit Sapling Foundation. Rodriguez recalled how she and other mothers realized how much they had in common with el-Wafi. Despite their nervousness at meeting the mother of an alleged plotter it was a great success. "I got sympathy after the tragedy, but Aicha's suffering is equal to mine," she said.
On her organization's website, Rodriguez has written of her admiration for el-Wafi. "The day I met Aicha was the day that changed my life because it changed my direction emotionally. It was the beginning of my learning that someone like Aicha, who has suffered so much, could still be emotionally generous. It brought out the generosity in me and I felt better for it.
"Meeting Aicha gave me strength and took away my anger and bitterness. It has also helped me to forgive myself, because a mother always feels guilty when things don't go right for her children."
Rodriguez said she also believed Moussaoui was the victim of a miscarriage of justice. "Zacarias is an admitted member of al Qaeda, but there's no evidence that he knew anything about the attacks on the World Trade Center. He pleaded guilty either because he felt it would get him more humane conditions of confinement or because he was in no fit state to make any rational decisions.
"When I watched Zacarias at the trial my heart was broken because I could not look at him as a stranger. I saw him as the son of my friend Aicha."