Osama bin Laden has exploited Britain's global reputation as a sanctuary for political refugees to establish a power base of fund-raising and recruitment activity.
The presence in London of hundreds of dissidents of Arab regimes, some of them veterans of the Afghan wars, has created a hotbed of Islamic fundamentalist opinion. And it is from among these hardline opponents of the governments of Egypt, Jordan, Saudi Arabia, Algeria and other parts of the Arab world that Mr bin Laden's al-Qa'ida organisation has found a vein of support.
Today at Bow Street magistrates' court, a London-based Algerian, Amar Makhlulif, 36, will face extradition to the United States accused of conspiring to cause explosions.
Mr Makhlulif, who is also known as "The Doctor" or Dr Haydar Abu Doha, has been named by American prosecutors as a key figure in Mr bin Laden's network and a mastermind of a millennium plot to blow up Los Angeles airport.
The complaint alleges that Mr Makhlulif helped terrorists to travel to training camps in Afghanistan run by al-Qa'ida and sent others to Canada in preparation for the thwarted attack.
Ahmed Ressam, another Algerian who was later jailed for his role in the planned bombing, was arrested in Seattle in December 1999.
American police, who searched Ressam's car, found a business card with a London telephone number appearing to belong to Mr Makhlulif. A search of Mr Makhlulif's home allegedly turned up several passports, fake identification documents and papers with chemical notations for explosives similar to those found in Ressam's car.
But Mr Makhulif and other Arab dissidents in Britain have an uneasy relationship with the larger, mostly Pakistani, British Muslim community. Inayat Bunglawala, a spokesman for the Muslim Council, said most British Muslims were "deeply apprehensive" of Mr bin Laden and other extremists.
Yet a London-based Arab journalist, Samir al-Mubarak, said Britain's importance in raising funds and recruitment for Mr bin Laden's cause was "well-known". "[Britain] is not only a station for funding and financial transfers for the fundamentalist movements, but it is also an investment region for them.... Nobody can deny that [Mr bin Laden] has investments in companies and real estate."