They kidnap Westerners in the deserts of Africa, turn Western-born Muslims into radicals, send bombs to the United States from Yemen and mount bloody attacks in Iraq and Pakistan.
These homegrown terror groups worldwide are informally dubbed al-Qaida franchises _ affiliates that do most of their own fundraising, recruiting and killing. The question now is this: What impact will the death of al-Qaida leader Osama bin Laden have on the ability and willingness of the franchises to mount attacks?
Emails found on flash drives from bin Laden's hideout in Pakistan two weeks ago show that he was communicating more than Western intelligence had thought. But al-Qaida's ideology plays a much bigger role in fostering terror than bin Laden's personal involvement, said Gen. David Richards, Britain's top military chief.
"Yemen, Somalia and other places in the Middle East are today more important in a counter-terror context than what was going on...in Osama's compound," Richards told British lawmakers.
Several al-Qaida franchises have vowed retaliation for bin Laden's death, but it's unclear how much of a threat they pose. The biggest terrorist plots to date have been pulled off or directed by al-Qaida itself, including the Sept. 11 attacks and the 2005 London suicide bombings.
However, al-Qaida franchises were responsible for the 2008 attacks in the Indian city of Mumbai that killed 166, and the 2002 attacks on a Bali island night club that killed 202 people, many foreign tourists.
The head of Britain's domestic spy agency MI5, Jonathan Evans, has said it's only a matter of time before "we see terrorism on our streets" from the al-Qaida movement in Somalia, known as al-Shabab. He also said it is likely that al-Qaida supporters in the Arabian Peninsula will step up attacks on Western targets.
The fight to bring down al-Qaida franchises will depend on painstaking coordination among intelligence agencies worldwide. Rohan Gunaratna, who heads the Center for Political Violence and Terrorism Research in Singapore, predicted that al-Qaida and the franchises are "likely to pose an enduring threat in the foreseeable future."
Al-Qaida now has about 10 major franchises, although the Afghanistan-Pakistan group has splintered into smaller and more dangerous ones. Al-Qaida provides ideological inspiration and sometimes direct training and funding. The franchises have goals within their own regions but also international aspirations, which include U.S. and European targets.
Among the first franchises to spring up was al-Qaida in Iraq in about 2003, formed to attack U.S. forces. However, this franchise took some of the luster off al-Qaida's message because of its massacre of thousands of Shiite Muslims.
Al-Qaida in Iraq is now thought to be much smaller than in its heyday, although there is no reliable estimate on the number of members. Yet in a show of strength, a front group called the Islamic State of Iraq boasted recently that extremists had slipped guns and messages to inmates for weeks before an unsuccessful prison break that left 17 dead.
Three days before the attempted jail breakout, the group staged a suicide bombing at an Iraqi police station in which 20 officers died. On the same day that it claimed responsibility for the bombing, it called for revenge for bin Laden's death.
"The martyrdom of the sheik will increase the determination and steadfastness among his brotherly mujahideen," read the statement, signed by Abu Bakr al-Husseini al-Baghdadi, a pseudonym for the militant whom the U.S. identified Wednesday as taking the helm of the Islamic State of Iraq.
The al-Qaida faction in Yemen is viewed as perhaps the most threatening to the United States and some European countries because of its history of attempted attacks. It is believed to be responsible for the failed 2009 bombing of a Detroit-bound airliner by a suicide bomber with explosives sewn into his underwear, along with last year's unsuccessful plot to send mail bombs on U.S.-bound cargo planes.
The Yemen faction has taken advantage of protests calling for the ouster of longtime president Ali Abdullah Saleh to build up strength in the country's weakly-governed provinces. On Tuesday, two armed men thought to belong to al-Qaida opened fire on security posts outside the town of Mukalla, killing three people.
The al-Qaida offshoot in Yemen has been boosted by inspiration from American-born operative Anwar al-Awlaki, who has radicalized a younger generation of extremists. A British woman who stabbed a lawmaker last year had watched about 100 hours of al-Awlaki videos, British officials said. Al-Awlaki is also believed to have inspired and even plotted or helped coordinate attacks on the U.S., including the failed 2009 airline bombing and last year's mail bombing.
In Somalia, the al-Shabab Qaida offshoot taxes ships coming into port, extorts portions of crops from farmers and has links to pirates. It is putting out increasingly sophisticated propaganda, with flashy videos in English featuring a rapping American named Omar Hammami, one of around 20 American members of Somali descent. Hammami, known as Abu Mansur al-Amriki, or "the American," said at a news conference last week that militants would seek revenge for the death of Osama bin Laden.
Also of threat to Europe is another al-Qaida faction that is raising tens of millions of dollars via kidnappings and ransom in Algeria, Mali, Mauritania, Niger and Libya. This group, known as al-Qaida in the Islamic Maghreb, targets France and seeks to overthrow the Algerian government, seen as a key defense against terror attacks in Europe just across the Mediterranean Sea.
Mathieu Guidere, a professor at University of Toulouse who trained French military officers to monitor al-Qaida communiques, puts the group's income since 2008 at a staggering $72 million. Ransom is set according to each captive's nationality, with Americans and Canadians fetching $2.5 million to $5 million each and starting prices for French captives at about $2 million.
Bin Laden's death could help recruit poor youth, said an Arab leader from Mali's Timbuktu region, where al-Qaida of the Maghreb recruits actively and openly. But it could also prompt recruiters to be more careful so they don't attract attention, said the leader, who spoke on condition of anonymity to avoid possible retributions.
Intelligence officials say al-Qaida Maghreb ransom money has funded regional terror attacks, including the December 2007 double truck bombings of the U.N. headquarters in Algiers that killed 17 employees. That came eight months after a bomb targeting the prime minister's office killed 33 people.
A witches' brew of militant groups operate in Pakistan's tribal regions, all with varying degrees of loyalty to and interaction with al-Qaida.
Leading among them are Lashkar-e-Taiba, blamed for the Mumbai attacks, and the brutal Lashkar-e-Janghvi, believed to supply the reservoir of suicide bombers used in Pakistan and Afghanistan. It was Lashkar-e-Janghvi's Qari Hussein whom U.S. intelligence believes trained the Jordanian suicide bomber who blew up the six CIA officials at Camp Chapman in December 2009. Al-Qaida gives ideological training and funding to Lashkar-e-Janghvi militants, according to Western intelligence officials.
Pakistan is also key ground for terror candidates from Europe, the United States, Canada, Turkey and central Asia, who are often organized by groups with al-Qaida links. They return home and operate as small and fractured cells, recruiting jihadists, raising funds and plotting small-scale attacks.
German authorities believe the biggest threats come from individual agents who are difficult to monitor because they radicalize on their own, through Islamic Websites and social networks on the Internet. They cite the example of 21-year-old Arid Uka, who stormed a U.S. military bus at Frankfurt airport last month before bin Laden's death, fatally shooting two U.S. airmen.
In Southeast Asia, hundreds of the most dangerous radicals were killed or captured in Indonesia, Malaysia, Singapore, Thailand and the Philippines before bin Laden's death. But the Indonesia-based Jemaah Islamiyah, Southeast Asia's main extremist group, its offshoots and the smaller Abu Sayyaf in the southern Philippines have tenaciously survived largely on their own and persist as major threats.
Police and foreign governments have said that Jemaah Islamiyah used al-Qaida money to fund the 2002 Bali nightclub bombings that killed 202 people. But it's unclear how much influence al-Qaida still wields on Indonesian militant groups, which are constantly splintering and morphing.
Most experts say the financial links have been severed and that July 2009 suicide bombing of two glitzy hotels in Jakarta, the Indonesian capital, was financed locally.
Indonesia's best-known radical cleric, Abu Bakar Bashir, co-founded Jemaah Islamiyah with the goal of establishing an Islamic state in Southeast Asia. He predicted bin Laden's death will prompt a major disaster to Americans that will "definitely happen, but when and how big, only God knows that."
Matthew Levitt, a counterterrorism and intelligence expert at the Washington Institute for Near East Studies, said al-Qaida franchise leaders must be spooked by the possibility that U.S. intelligence obtained during the raid on bin Laden's compound could prompt strikes against them. But the fundraising mechanisms are still goings strong, and any big news, bad or good, could help raise funds. They could also use bin Laden's death as a marketing strategy, he said.
"You could imagine someone going around with a bin Laden clip on their cell phone, that would be a great photograph to use for a fundraising pitch," he said. "The bottom line is, bin Laden as an advertising icon is as potentially effective in death as he was in life, maybe even more so."
Contributing to this story: Paisley Dodds in London; Melissa Eddy in Berlin; Katharine Houreld in Nairobi, Kenya; Martin Vogl in Bamako, Mali; Barbara Surk in Dubai, United Arab Emirates; Rebecca Santana in Baghdad; Jim Gomez in Manila, Philippines; Kathy Gannon in Islamabad; Robin McDowell in Jakarta, Indonesia.