This document does not contain all the material known to the Government, because of the absolute need to protect intelligence.
Osama bin Laden and al Qaeda have been based in Afghanistan since 1996, but have a network of operations throughout the world. Al Qaeda and the Taliban regime have a close and mutually dependent alliance.
Osama bin Laden and al Qaeda provide the Taleban regime with material, financial and military support. They jointly exploit the drugs trade.
The Taleban allow bin Laden to operate his terrorist training camps and activities from Afghanistan, protect him from attacks from outside, and protect the drugs stockpiles. Osama bin Laden could not operate without the alliance and support of the Taleban.
Osama bin Laden has claimed credit for the attack on US soldiers in Somalia in October 1993, which killed 18, for the attack on the US Embassies in Kenya and Tanzania in August 1998 which killed 224 and injured nearly 5000, and was linked to the attack on the USS Cole on October 12 last year, in which 17 crew members were killed and 40 injured.
After September 11 we learned that, not long before, bin Laden had indicated he was about to launch a major attack on America. The detailed planning for the terrorist attacks was carried out by one of bin Laden's close associates.
Of the 19 hijackers involved, it has already been established that at least three had links with al Qaeda.
The attacks were similar in both their ambition and intended impact to previous attacks undertaken by Osama bin Laden and al Qaeda, and also had features in common.
In particular: Suicide attackers, coordinated attacks, the aim to cause maximum American casualties, total disregard for other casualties, including Muslim, meticulous long-term planning, absence of warning.
Osama bin Laden has provided the Taleban with troops, arms and money to fight the Northern Alliance. He is closely involved with Taleban military training, planning and operations.
He has representatives in the Taleban military command structure. He has also given humanitarian aid. Forces under his control have fought alongside the Taleban in the civil war.
Since 1996, when the Taleban captured Kabul, the US Government has consistently raised humanitarian and terrorism issues with them.
Well before September 11, they provided evidence to the Taleban of the responsibility of al Qaeda for the terrorist attacks in East Africa.
The US had made it clear to the Taleban that al Qaeda murdered US citizens, and planned to murder more. The US offered to work with the Taleban to expel the terrorists.
In June 2001, in the face of mounting evidence of the al Qaeda threat, the US warned the Taleban that it would hold the regime responsible for attacks against US citizens by terrorists in Afghanistan.
The US had the support of the United Nations.
The Taleban responded by saying no evidence existed against bin Laden, and he would not be expelled.
A former Government official in Afghanistan has described the Taleban and bin Laden as "two sides of the same coin".
Osama bin Laden has urged and incited his followers to kill American citizens.
On October 12 1996 he issued a declaration of jihad:
"The people of Islam have suffered from aggression, iniquity and injustice imposed by the Zionist-Crusader alliance and their collaborators ...
"It is the duty now on every tribe in the Arabian peninsula to fight jihad and cleanse the land from these Crusader occupiers. My Muslim brothers: your brothers in Palestine and in the land of the two Holy Places [i.e. Saudi Arabia] are calling upon your help and asking you to take part in fighting against the enemy the Americans and the Israelis."
That same year he said that: "terrorising the American occupiers [of Islamic holy places] is a religious and logical obligation".
In February 1998 he issued and signed a 'fatwa', which included a decree to all Muslims:
" ... the killing of Americans and their civilian and military allies is a religious duty for each and every Muslim, to be carried out in whichever country they are until Al Aqsa mosque has been liberated ... "
In an interview aired on Al Jazira [Doha, Qatar] television he stated:
"Our enemy is every American male, whether he is directly fighting us or paying taxes."
In two interviews broadcast on US television in 1997 and 1998, he referred to the terrorists who carried out the 1993 attack on the World Trade Center as "role models".
From the early 1990s bin Laden has sought to obtain nuclear and chemical materials.
Based on our experience of the way the network has operated, other cells, like those that carried out the terrorist attacks on September 11, must be assumed to exist.
Al Qaeda functions on its own and through other terrorist organisations.
These include Egyptian Islamic Jihad and other north African Islamic extremist terrorist groups, and a number of other jihadi groups in other countries including the Sudan, Yemen, Somalia, Pakistan and India.
Below bin Laden is a body known as the Shura, which includes representatives of other terrorist groups.
In addition to the Shura, al Qaedaal-Qaeda has several groups dealing with military, media, financial and Islamic issues. Mohamed Atef is a member of the group that deals with military and terrorist operations. His duties include principal responsibility for training al Qaeda members.
In 1992 and 1993 Mohamed Atef travelled to Somalia on several occasions for the purpose of organising violence against US and UN troops. On each occasion he reported back to bin Laden, at his base in the Riyadh district of Khartoum.
In the spring of 1993 Atef, Saif al Adel, another senior member of al Qaeda, and others began training Somali tribes to fight the UN forces.
On October 3 and 4 1993, operatives of al Qaeda participated in the attack on US military personnel serving in Somalia as part of the operation 'Restore Hope'.
From 1993, members of al Qaeda began to live in Nairobi and set up businesses there. They were regularly visited there by senior members of al Qaeda, in particular Atef and Abu Ubadiah al Banshiri.
In the latter part of 1993, members of al Qaeda in Kenya began to discuss attacking the US Embassy in Nairobi in retaliation for US participation in Operation Restore Hope in Somalia.
Ali Mohamed, a US citizen and admitted member of al Qaeda, took photographs and made sketches of the US embassy, which he presented to bin Laden in Sudan.
In June or July 1998, two al Qaeda operatives, Fahid Mohammed, Ali Msalam and Sheik Ahmed Salim Swedan, purchased a Toyota truck and made alterations.
In early August 1998, operatives of al Qaeda gathered in 43, New Runda Estates, Nairobi, to execute the bombing of the US Embassy.
On 7 August 1998, Assam, a Saudi national and al Qaeda operative, drove the Toyota truck to the US embassy. There was a large bomb in the back of the truck.
Map: Opposing forces in the war against terror
Afghanistan facts and links
Full coverage: Terror in America