Al-Qaeda (Arabic for "the base") is a worldwide Sunni Islamist militant insurgent group. Founded by Osama bin Laden in 1988 in Afghanistan, al-Qaeda is now dedicated to driving the United States out of the Middle East specifically and out of Muslim countries generally, to destroying Israel, and to toppling pro-Western governments in Islamic countries and replacing them with Islamic fundamentalist governments.

These three goals lead to the organization’s ultimate goal, which is the reestablishment of the caliphate, a nation uniting Muslims and spanning the Islamic world.

The organization is believed to be highly redundant, both financially and operationally. While the various cells that make up the organization are accountable to higher-level leadership, operations appear to be left to the individual cells, while higher levels provide material and logistical support.

Ideas and targets coming from the upper echelons filter down to the individual cells responsible for coordinating and executing the attacks. This redundancy increases the organization’s resiliency; when cells are destroyed or captured, the losses can be contained more effectively than if al-Qaeda were a more linear organization.

Al-Qaeda’s training camps are likewise well organized. The extent of the training and organization is best seen in the group’s multivolume Encyclopedia of Jihad. Several thousand pages in length, the encyclopedia details the bureaucratic workings of the group.

Covered topics include guerrilla warfare, assembling booby traps, tactics for fighting against armored or aerial combat units, urban warfare, intelligence security, data gathering, and chemical weapons tactics.

The group has been linked to or accused of taking part in terrorist acts across the globe beginning in the early 1990s. A list of the attacks against U.S. interests attributed to al-Qaeda includes the 1992 hotel bombings in Aden, Yemen; the February 6, 1993, bombing of the World Trade Center in New York City; attacks carried out on U.S. military forces in Somalia in 1993 and 1994; the June 25, 1996, truck bombing of the Khobar Towers residential compound in Dhahran, Saudi Arabia; the near-simultaneous bombings of U.S. embassies in Nairobi, Kenya, and Dar es Salaam, Tanzania, on August 7, 1998; the suicide bombing of the USS Cole in Yemen on October 12, 2000; and the September 11, 2001, airline hijackings and attacks on the Pentagon and the World Trade Center.

The United States is not the group’s only target, however. Al-Qaeda also is linked to the April 2002 bombing of the El Ghriba synagogue in Tunisia; the October 2002 nightclub bombing in Bali, Indonesia; the November 2003 bombings of synagogues and a British bank in Istanbul, Turkey; the March 11, 2004, train bombings in Madrid, Spain; and the July 7, 2005, London transit bombings.

Al-Qaeda is most often represented and understood in regard to its founder, Osama bin Laden (aka Abu Abdallah). Bin Laden was born in Riyadh, Saudi Arabia, on March 10, 1957. When he was six months old, his father, Muhammad bin Laden, the Yemeni immigrant who established the Saudi Binladin Group, relocated to Jeddah, where Osama grew up.

The Soviet Union’s December 1979 invasion of Afghanistan galvanized the Muslim world in defense of Afghanistan and provided the West with a proxy war through which to combat the Soviet Union. Bin Laden, who had studied economics at King Abdul Aziz University in Jeddah, was one of many spurred to action in defense of Afghanistan.

He made his first trip to neighboring Pakistan in 1980, where he sought ways to contribute to the jihad. Bin Laden made several monetary contributions to the mujahideen, but quickly began looking for other ways to contribute.

Bin Laden joined with Palestinian cleric Abdullah Azzam to found the Services Bureau (Makhtab al-Khidimat, or MAK) in Pakistan in 1984. Azzam, who had taught at King Abdul Aziz University while bin Laden studied there, was indispensable in recruiting.

In addition to providing relief to war victims in Afghanistan, the MAK organized and coordinated the volunteers, donations, and weapons coming into Pakistan and Afghanistan in support of the jihad.

Azzam believed that the young Arab men streaming to Pakistan to participate in the jihad should be scattered among the Afghan functions. Azzam felt that such a mixing of Arabs among the local forces would reap benefits both in Afghanistan and abroad.

Bin Laden saw the situation differently and sought to create his own separate Arab fighting force. He believed that such a force would be a superior fighting unit compared to local Afghan forces. Bin Laden broke with Azzam and established training camps for his Arab force near Jaji, in eastern Afghanistan.

From this base, which they dubbed al-Masadah (the Lion’s Den), bin Laden’s "Arab Afghans" engaged the Soviets in the battle of Jaji in the spring of 1987. It was at this time that bin Laden grew closer to the Egyptian Islamic Jihad (EIJ) and one of its most prominent members, Ayman al Zawahiri, who would become bin Laden’s deputy in al-Qaeda.

When the Soviets announced their planned withdrawal in April 1988, bin Laden began preparations to perpetuate and expand his forces. He began by moving his unit to the area around Jalalabad, Afghanistan, which became known as al-Qaeda; bin Laden would later say that the name remained with the group by accident. Following the Soviet withdrawal in 1989, bin Laden returned to Saudi Arabia.

When Saddam Hussein invaded Kuwait on August 2, 1990, bin Laden, who had consistently expressed his contempt for the "atheist" Hussein and his Ba’athist government, approached the Saudi king with a plan to use his Arab Afghans to drive Hussein’s forces from Kuwait.

The Saudi government sought to restrict his movements within the kingdom. Bin Laden obtained permission in early 1991 to travel to Pakistan on the pretext of checking in on some business interests and never returned to Saudi Arabia.

In early 1992 bin Laden and al-Qaeda moved to Sudan, where they remained until 1996. Al-Qaeda and the National Islamic Front (NIF), the ruling party in Sudan, enjoyed a symbiotic relationship.

The NIF granted al-Qaeda a safe haven and freedom of movement, while bin Laden made substantial investments in Sudanese industry and agriculture and undertook several large-scale construction projects to develop the infrastructure and agricultural and industrial production capacity of Sudan.

While in the Sudan, bin Laden directed his forces in actions against the communist government of South Yemen. The Arab Afghans also were sent to Bosnia, where they had a substantial impact on that conflict. Bin Laden dispatched al-Qaeda forces into Somalia in response to the buildup of U.S. forces.

In December 1992 President George H. W. Bush sent 28,000 U.S. troops into Somalia on a humanitarian mission in support of United Nations (UN) relief efforts. Bin Laden and al-Qaeda dismissed all humanitarian claims and interpreted the U.S. presence as a way of putting pressure on Islamic regimes and as an effort to establish another base from which to attack Muslim nations.

Al-Qaeda regarded Yemen as a major victory. First, even though the hotels bombed in Yemen did not house U.S. personnel, the transfer of U.S. troops out of Yemen shortly after the hotel bombings indicated to al-Qaeda that they had been successful in driving the Americans from Yemen.

Bin Laden also claimed that the militarily superior U.S. forces were driven from Somalia by a poor, ill-armed people whose only strength was their faith. In his 1996 fatwa declaring war against the United States, bin Laden claimed that the most important lesson to be learned from Somalia was that the United States would flee at the first sign of resistance.

The year 1994 was a watershed for bin Laden. He survived two assassination attempts and in April was stripped of his Saudi citizenship in response to the growing threat he represented to the regime.

A final step in his radicalization came in August, when the Saudi government imprisoned clerics Salman al Awdah and Safar al Hawali, who were among the first and most prominent of the clerics circulating cassettes of their sermons against the continued U.S. presence in the Arabian Peninsula, and whose imprisonment bin Laden would later mention in his 1996 fatwa.

Bin Laden and al-Qaeda left Sudan in 1996 and returned to Afghanistan, a move prompted by several factors. In addition to the assassination attempts, bin Laden faced international pressure on the NIF and its de facto leader, Hassan al-Turabi.

The United States and Saudi Arabia sought to have bin Laden silenced and his activities curtailed, and al-Turabi found it increasingly difficult to maneuver and protect bin Laden.

When Sudan started pressuring bin Laden, he returned to Jalalabad. There bin Laden and al-Qaeda entered into a symbiotic relationship with the Taliban ("the students"), who were in the process of consolidating their control over much of the country.

This relationship was similar to that with the NIF in Sudan; bin Laden and his organization gained considerable freedom of movement and protection, while his benefactors benefited from agricultural, infrastructural, and industrial investment and development.

It was during the period between bin Laden’s return to Afghanistan and the 1998 fatwa that civilians became targets. Both the 1996 fatwa and bin Laden’s 1997 CNN interview spoke of civilians as collateral damage, not as legitimate targets in and of themselves.

By 1998 this had changed, and the fatwa issued February 22, 1998, explicitly stated that Americans and their allies, civilians and military alike, were now al-Qaeda targets anywhere they could be found.

Communications from al-Qaeda repeatedly stress their belief that Western governments oppress Muslims and Muslim nations and are engaged in a war against Islam. Bin Laden describes the presence of U.S. forces in "the Land of the Two Holy Places" (Saudi Arabia) as the greatest insult and threat faced by the Islamic world since Muhammad’s lifetime.

In addition to decrying U.S. support for Israel, the group condemns U.S. support for what it considers "apostate regimes", particularly Egypt and Saudi Arabia. Bin Laden also points to the sanctions imposed on Iraq following the Gulf War as one reason to reject any human rights arguments coming from the West.

Al-Qaeda’s idea of the ummah (community of believers; the Islamic world) in opposition to the world derives from the teachings of two prominent Islamic scholars.

Ibn Taymiyyah (1263–1328) was a 14th-century Islamic scholar who taught that jihad is the duty of each individual Muslim when Islam is attacked, that the Qu’ran should be interpreted literally, and that all Muslims should read the Qu’ran and Hadith (the sayings of the Prophet) for themselves and not rely on a learned clergy. A second influence on al-Qaeda was Sayyid Qutb (1906–66), an Islamist associated with the Egyptian Muslim Brotherhood.

Describing the world as existing between states of belief (Islam) and unbelief (jahiliyya), Qutb condemned Western and Christian civilization. Urging jihad against all enemies of Islam, Qutb believed that there is no middle ground and that all Muslims must take to jihad when Islam is threatened.

These influences are apparent in al-Qaeda’s activities and rhetoric. Bin Laden believes that since the Christians, Jews, and Hindus have nuclear weapons, it is only fitting that Muslims obtain them as well.

Bin Laden also echoes Ibn Taymiyyah in his assertions that the Saudi government is aiding the "crusaders" in plundering the wealth of the ummah, the vast Middle Eastern oil reserves, and by acting to keep oil prices below fair-market value.

Al-Qaeda’s leadership cadre is well educated. Bin Laden has a university degree in economics, and his inner circle contains doctors; agricultural, civil, and electrical engineers; and computer scientists, but no religious scholars.

Rahman’s fatwa echoed the call to attack the United States and its allies—civilian and military, anywhere in the world—and contained exhortations to sink ships, shoot down airplanes, and burn corporations and businesses.

Two separate attacks on U.S. warships were made in subsequent years, with the USS Cole attack following an unsuccessful attack on the USS The Sullivans one year earlier. On September 11, 2001, the plot masterminded by Ramzi Binalshibh and Khalid Sheikh Mohammed, who were arrested in Pakistan in 2002 and 2003, respectively, proceeded along the lines of Rahman’s fatwa.