By Tom Pfeiffer and Marwa Awad
CAIRO (Reuters) - The man most likely to take the helm of al Qaeda after Osama bin Laden did not emerge from the crowded slums of Egypt's sprawling capital or develop his militant ideas in any religious college or seminary.
Instead, Egyptian-born Ayman al-Zawahri was raised in Cairo's leafy Maadi suburb amid the comfortable villas that are popular with expatriates from the Western nations he rails against. He studied at Cairo University and qualified as a doctor.
The son of a pharmacology professor was not unique in his generation. Many educated youngsters were outraged at the treatment of Islamists in the 1960s when Egypt veered toward a Soviet-style one-party state under socialist Gamal Abdel Nasser.
Thousands of people suspected of subversion were thrown into prison after show trials. One of the young Zawahri's heroes, Muslim Brotherhood luminary Sayyid Qutb, was executed in 1966 on charges of trying to overthrow the state.
"Zawahri is one of the many victims of the Nasser regime who had deep political grievances and a feeling of shame at Egypt's defeat by Israel in 1967. He grew up a radical," said Khalil al-Anani, an expert in Islamist movements at Durham University.
He rose to be al Qaeda's No. 2, making him a prime candidate to lead the network after Osama bin Laden was killed in a firefight with U.S. forces at his Pakistan hideout on Monday, almost 10 years after the September 11 attacks on the United States.
Born in 1951 to a prominent Cairo family, Zawahri was a grandson of the grand imam of Al Azhar, one of the most important mosques in the Muslim world.
As he studied for a masters in surgery in the 1970s, Zawahri was active in a movement that later became Islamic Jihad, which aimed to expel the government and establish an Islamic state.
People who know Zawahri disagree over whether he was destined by temperament for militancy or pushed into it as a protest against state oppression of Egyptian Islamists.
A heavy-handed Egyptian security policy designed to weaken Islamism nudged its members further toward violent action, as young men rounded up in state security sweeps revolted against what they saw as unfair treatment.
Zawahri was one of hundreds tried for links to the 1981 assassination of President Anwar Sadat, Nasser's successor. He served a three-year jail term for illegal arms possession, but was acquitted of the main charges.
"Zawahri was not given a chance to be part of politics," said his lawyer Nizar Ghorab.
"He lived during a time of great suppression of those who had religious ideas and wanted to change the political scene of oppression under Nasser and Sadat."
People who studied with Zawahri at Cairo University's Faculty of Medicine in the 1970s describe a lively young man who went to the cinema, listened to music and joked with friends.
"When he came out of prison he was a completely different person," said one doctor who studied with Zawahri and declined to be named.
Others say that what tipped Zawahri into political violence was Iran's 1979 Islamic Revolution and Sadat's peace treaty with Israel the same year.
"There was an evolution in his mentality," said Anani. "People like Zawahri saw no way to achieve their goals except to changing the regime by force."
Zawahri's nephew Abdel Rahman al-Zawahri, 26, an accountant, said: "I do not think that what drove my uncle to choose the path he chose resulted from his years in prison or the torture he experienced. He is a thinker and he had an idea and ideology."
On his release, Zawahri went to Pakistan where he worked with the Red Crescent treating Islamist mujahideen guerrillas wounded in Afghanistan, which Russia had invaded in 1979.
"In his childhood and as a young man he was cheerful and had a sense of humor," said Zawahri's uncle, Mahfouz Azzam. "His years spent along the border as a war surgeon during the war in Afghanistan changed his views about how change and resistance can happen."
"KNOWN AND RESPECTED" ZAWAHRI FAMILY
Taking over the leadership of Jihad in Egypt in 1993, Zawahri was a key figure in a violent campaign in the mid-1990s to set up a purist Islamic state there, in which more than 1,200 Egyptians died.
In 1999, an Egyptian military court sentenced Zawahri to death in absentia. By then he had swapped his comfortable suburban background for the Spartan life of a holy warrior.
John Brennan, counter-terrorism adviser to President Barack Obama, said on Tuesday that Zawahri, who was al Qaeda's chief organiser under bin Laden, was believed to be living in Pakistan or Afghanistan, and was still being hunted.
A doorman in the street in Cairo's Maadi district where Zawahri's brother lives said the Zawahri family owns a hotel in the neighborhood. The family is "known and respected," he said. "They are always cheerful and sociable and very generous."
Starbucks and Costa coffee shops have become popular haunts for residents of Maadi. The shops cater for the many Americans and other expatriates who live there, selling imported Oreo biscuits, Dr Pepper drinks and microwave popcorn packets.
Many of the U.S. expatriates work for American oil companies or at the U.S. embassy, the largest permanently staffed U.S. mission and testimony to U.S. ties and a $1.3 billion-a-year military aid program agreed after the peace deal with Israel.
Sadat signed the peace deal and his successor Hosni Mubarak built on the alliance during three decades in office that came to an end on February 11 this year in a popular uprising.
Al Qaeda, which had inveighed against Western-backed Arab autocrats, was nowhere in sight in those protests. Instead the rallies were led by youths, many with a broadly secular agenda and who used Twitter and Facebook to rally the crowds.
Zawahri's sister was among those who massed in Cairo's central Tahrir Square.
"The peaceful revolutions in the Arab world are a huge defeat for Al Qaeda and its ideas," said Durham analyst Anani.