Some held their heads in their hands. Others wept openly. A few stared straight ahead.  

It was the end of the 11 September commission's public hearings and those in the cavernous auditorium in Washington knew that they had just heard the final, definitive account of the world-changing events 33 months before.

They had heard a story that shattered myths and provided few comforts. They had heard of the chaos in the administration and air defence systems on that fateful morning; they had heard of the failures of the security services of the most powerful state in history; they had heard from inside the terrorist cell that hatched -- and successfully executed -- the most ambitious attack ever. They had heard the truth at last.

For some, the proceedings brought calm. Others remain angry. "There's an invisible wound in my heart that can only be closed with truth and by someone accepting responsibility," said April Gallop, who survived being buried in the rubble of the Pentagon.

The commission, an independent, bipartisan panel formed by primary legislation and the reluctant signature of the president, has interviewed hundreds of officials, intelligence experts and politicians, including George Bush.

It owes its existence to pressure from relatives of those who died on September 11, 2001, and thus has the moral power to force powerful figures to testify before it. They revealed that the terrorists owed their success, at least in part, to the confusion, errors in judgment and laziness of those charged with defending America.

The story starts in Pakistan where, in the 1980s, thousands of young Arabs gathered to aid the Afghans in their war with the Soviet Union. Some, such as Osama bin Laden, tall, handsome scion of one of the Gulf's richest families, were minor celebrities. Others, such as Khaled Sheikh Mohammed, a tubby young Pakistani engineer, shunned the limelight.

When the Russians withdrew in 1989, many militants, including Mohammed, turned their attention to another superpower supposedly set on the domination and humiliation of Islam: America. Over the next few years Mohammed worked contacts in Pakistan and among wealthy sympathizers in the Gulf, sourcing funding and volunteers for a wide range of terrorist operations against US targets.

One involved a young Pakistani called Ramzi Yousef, who in 1993 tried and failed to blow up the World Trade Center.

But no one was paying much attention. In 1994 Mohammed moved to Manila in the Philippines, where he hooked up with Yousef again for an ambitious attempt at a long-standing pet project: the simultaneous destruction of a number of civilian passenger jets. The process that would lead to September 11 had begun.

At first things went badly wrong. A fire led police to the flat where Mohammed's team were making bombs. Yousef fled -- and was caught in Pakistan. Mohammed escaped to Qatar to lie low. Hounded by US intelligence agents, Mohammed was forced to move on again, to Afghanistan.

In late 1996, according to the commission, Mohammed went to bin Laden and pitched his grand idea: to hijack 10 planes in America and crash nine into the headquarters of the CIA and the FBI, the tallest buildings on the East and West Coasts, and into nuclear plants.

Mohammed himself would hijack one plane, kill all males on board, land it, release the women and children, then denounce American policies in the Middle East at a press conference. Bin Laden did not commit himself. Not yet.

In early 1999 Mohammed was summoned to Kandahar, the southern Afghan desert city where bin Laden and the Taliban had their headquarters. His plan was on.

Following the attacks in Africa, President Bill Clinton authorized the killing of bin Laden. Three times in the next 18 months air strikes to kill him in Afghanistan were cancelled at the last minute, despite bin Laden being "in the cross-hairs."

This was at the end of Clinton's term and, despite warnings of terrorism threats aimed at the United States, incoming officials thought the departing "Clintonites" were terrorism-obsessed. Contact with the Taliban, aimed at forcing them to give up bin Laden, dropped away. On May 8, 2001, Bush announced a task force headed by Vice President Dick Cheney to develop action on counter-terrorism. It never met.

Khaled Sheikh Mohammed had his own problems. Bin Laden had given him four experienced terror operators to complete his plan, but two were refused entry to the United States. Worse, the two Saudis who had made it to San Diego were unable to speak English and unlikely to be able to complete the flight training they needed.

Then came a breakthrough. Four young Arabs, who had been living in Germany, arrived in Afghanistan seeking training to fight in Chechnya. All spoke decent English and were used to the West. If they could be trained as pilots, they would be perfect.

By early 2000 they were back in Hamburg with instructions to get visas, go to the United States and start flying. Their targets, decided at a meeting with bin Laden himself, were to be the World Trade Centre, the Pentagon and the Capitol. And their leader, appointed personally by the terrorist mastermind, was a 30-year-old Egyptian called Mohamed Atta. By mid-2000, three of the four were in the United States. With the two Saudis on the West Coast, al-Qaeda had five operatives in place, all learning to fly.

One thing went smoothly, however. The camps in Afghanistan were able to provide a trained pilot and 19 young men, all of whom arrived in America during the spring and summer of 2001. Mohammed resisted pressure from bin Laden to strike in the early summer.

Bush briefed

On July 10, 2001, Kenneth Williams, an FBI agent in Phoenix, Arizona, sent a memo to the agency's headquarters. He was suspicious about the actions of some Middle Eastern students at a local flight school. He thought that terrorists might be trying to infiltrate the civil aviation system. His memo was ignored.

But there were other clues. One of the most explosive and contentious pieces of information revealed by the commission was a secret briefing given to Bush on August 6, 2001.

The document, declassified only after intense pressure, was titled "Bin Laden determined to attack inside the United States." Without being specific, it warned that al-Qaeda was trying to send operatives to the United States through Canada to carry out an attack using explosives, was looking at ways to hijack planes and may have had a support network in the country.

There were other warnings during that long, hot summer. On August 16, Zacharias Moussaoui was arrested for suspicious activity at a flight school. Moussaoui piqued the interest of the FBI after showing little interest in learning to take off or land. Incredibly, his arresting agent wrote he was the "type of person who could fly something into the World Trade Centre." Another FBI agent on the case speculated that a large aircraft could be used as a weapon. Still no one connected the dots.

On September 4, as Washington was getting back to the business of government after the summer, Clarke held his long-awaited meeting about putting his anti-terror plan to the president. But the plan would never make it to the president's desk. The terrorists would strike first.

At 8:21 the transponder aboard American Airlines Flight 11 was turned off and controllers lost touch with the plane. Atta and his team of hijackers had taken control and killed the pilot and his cockpit crew.

At 8:24 came the first direct confirmation that the attacks were under way. Atta was heard from the ground.

"We have some planes," he said.

Four minutes later, the Federal Aviation Administration was told. Nine minutes after that, the military was informed. With this sort of attack, such delays were crucial.

When the FAA controller informed the Northeast Air Defences Sector (Neads), the military command centre, about the hijacking, he asked for fighter aircraft to be scrambled.

Is this real world or exercise?

"Help us out," he pleaded.

"Is this real world or exercise?" was the response.

"No, this is not an exercise, not a test," insisted the controller.

At 8:46 two F-15 fighters were scrambled from Otis Air Force Base to intercept Flight 11. But they were 150 miles away. And too late. Atta was seconds away from plunging his jet into the north tower of the World Trade Centre.

A few minutes later, Bush, visiting a school in Florida, was told a plane had hit the World Trade Centre. However, aides said it was a twin-engined craft and pilot error was suspected. He continued with his visit in an air of normality. For him, the world had not yet changed.

That was not the case at the FAA. Controllers were already frantically worried by Atta's reference to "planes" in the plural. Did that mean more jets were under threat? At 8:47, less than 60 seconds after the first crash, the transponder on United Airlines Flight 175 blinked off. It went unnoticed until 8:51, when a controller spotted the change and ordered it switched back on. There was no response. Seven minutes later one FAA controller in New York told another: "'We might have a hijack over here, two of them."

At 9:01, the FAA told Neads about the second plane. "Heads up, man, it looks like another one coming in," said another FAA official. Two minutes later, the second plane hit the south tower. Bush was informed of the disaster -- in front of the full glare of the cameras -- by an aide whispering in his ear that "America is under attack."

Just three minutes before Flight 175 hit its target, FAA officials in Indianapolis noticed that Flight 77 from Washington had disappeared from the radar. Controllers started notifying other official agencies that the craft had probably crashed. In fact, it too had its transponder switched off. The plane had turned around and was now heading right back towards America's capital

Fighter jets at Langley Air Force base were scrambled at 9.23 but, amazingly, were ordered into the air in the mistaken belief that Flight 11 was still in flight and headed in the wrong direction. At 9:32 am, when Flight 77 was detected on the radar again, heading for Washington, the Langley jets were too far away to help. An unarmed National Guard cargo plane was asked by the FAA to follow Flight 77. It was too late.

"It looks like that aircraft crashed into the Pentagon, sir," reported the crew. It was 9:38 am and the terrorists had scored three out of three.

But still it was not over. Ten minutes before Flight 77 hit the Pentagon, controllers in Cleveland had heard sounds of a struggle from United Airlines Flight 93 from Newark, New Jersey. Between 9:34 and 9:38, controllers moved several other aircraft out of the way as Flight 77 rose unexpectedly into the skies.

Frantic mobile phone calls from relatives and loved ones meant that the passengers were all too aware of their fate. Todd Breamer said a prayer with the phone operator on his mobile, then helped lead a passenger assault on the cockpit with the now famous phrase: "Let's roll."

At 10:03, Flight 93 crashed into the ground just outside the village of Shanksville, Pennsylvania. When it crashed, the Langley jets had stopped chasing the phantom Flight 11 and were chasing the phantom Flight 77 -- after it, too, had already crashed. Jets were now patrolling Manhattan, though no new attacks were to come. Incredibly the military was informed of the hijacking on Flight 93 at only 10:07, four minutes after its passengers had brought it down.

It had taken just under two hours in all. The world had changed. But, for now at least, the attack was over and the inability of the administration was to be exposed.

September 11 myths shattered Myth No. 1

Myth No. 1

A strong relationship existed between Baghdad and Osama bin Laden.

Colin Powell, US Secretary of State, said in a speech to the United Nations in February 2003: "Iraqis continued to visit bin Laden in his new home in Afghanistan. A senior defector says Saddam sent his agents to Afghanistan some time in the mid-1990s to provide training to al-Qaeda members."

Commission: "In 1994 bin Laden is said to have requested [help] but Iraq never responded... There have been reports that contacts also occurred (in Afghanistan after 1996) but they do not appear to have resulted in a collaborative relationship."

Myth No. 2

Mohammed Atta, the leader of the hijackers, met an Iraqi agent in Prague on 9 April, 2001.

James Woolsey, the former CIA director (and a close friend of many neoconservatives), said in October 2001: "The Czech confirmation (of the Prague meeting) seems to me very important... It is yet another lead that points toward Iraqi involvement in some sort of terrorism against the United States that ought to be followed up vigorously."

Commission: "Based on the evidence available -- including investigations by Czech and US authorities plus detainee reporting -- we do not believe that such a meeting occurred... We have no credible evidence that Iraq and al-Qaeda co-operated on attacks against the United States."

Myth No. 3

Al-Qaeda was involved in drug trafficking.

"(Al-Qaeda) activity includes substantial exploitation of the illegal drugs trade" - a press statement issued by the British Government in October 2001

Commission: "No persuasive evidence exists that al-Qaeda relied on the drug trade as an important source of revenue."

(China Daily via agencies, June 23, 2004)