It appears to confirm claims made this week by a former White House anti-terrorism aide, Richard Clarke, that warnings he gave in early 2001 regarding al Qaeda were ignored.
The preliminary report was published as the independent panel opened two days of public hearings into the attacks.
Secretary of State Colin Powell, his Clinton Administration predecessor Madeleine Albright, and current Defence Secretary Donald Rumsfeld were called to testify yesterday. Other senior figures from both administrations, including Clarke, will be called today.
The reports say the Clinton Administration apparently knew as far back as 1995 of suspicions about Khalid Sheikh Mohammed, a deputy to bin Laden who was to mastermind the September 11 attacks.
But Washington did not try to capture him until it had proof of his terror links and had indictments against him.
Similar legal concerns discouraged the US from trying to capture bin Laden, although his ties to terror had been known since at least 1995.
"From the spring of 1997 to September 2001, the US Government tried to persuade the Taleban to expel Osama bin Laden to a country where he could face justice," the report said. "The efforts employed inducements, warnings and sanctions. All these efforts failed."
The report revealed the dead-end avenues pursued by the Clinton White House.
Backed by the US, Saudi Arabian intelligence chief Prince Turki bin Faisal said he had negotiated an agreement with the Taleban to eject al Qaeda. That agreement apparently fell apart in September 1998 during talks in Afghanistan between Prince Turki and the Taleban leader, Mullah Omar.
In August that year the US embassies in Kenya and Tanzania were bombed and 224 people died.
Madeleine Albright told the commission that President Clinton and his team "did everything we could, everything we could think of, based on the knowledge we had, to protect our people".
But the Clinton Administration was blamed for not moving more decisively against al Qaeda despite evidence from 1995 and 1996 that it was behind a series of terror attacks against US targets.
Instead Clinton and his advisers dealt with the incidents primarily as criminal matters, leaving them to the CIA and the FBI.
Colin Powell conceded at the hearing that on taking power in January 2001, the new Administration received full briefings from Clinton officials making it clear that the threat from al Qaeda had not been successfully tackled and that it required attention. But no strategy was suggested.
"We were not given a counter-terrorism action plan by the previous Administration. The briefers ... conveyed to us the gravity of the threat posed by al Qaeda. But we noted early on that the actions the previous Administration had tried had not succeeded in eliminating the threat."
Clarke says in his book, Against All Enemies, published this week, that he approached Bush's National Security Adviser, Condoleezza Rice, in January 2001 and told her the only remaining option was military action against al Qaeda, including strikes against its fighters in Afghanistan.
Clarke says he warned Bush officials in a memo about the growing al Qaeda threat after the attack on the USS Cole in Yemen.
But he says he was put off by Rice, who "gave me the impression she had never heard the term [al Qaeda] before".
In its report, the commission confirmed that Clarke advised giving secret aid to the main rebel group in Afghanistan, the Northern Alliance, to help it unseat the Taleban.
It said the advice was rejected by Rice and her deputy, Stephen Hadley, who opted for a broader review of the threat.
The results were presented to President Bush weeks before the September 11 attacks.
Rice declined to testify at the hearings.
The report also said that a day before the September 11 attacks, a meeting of US Cabinet officials had agreed on a three-pronged strategy to force bin Laden out of Afghanistan. The third of these prongs was the forcible overthrow of the Taleban.
Rumsfeld defended the Administration's failure to prevent the September 11 attacks.
"A terrorist can attack any time any place, and we can't defend at any time, any place ... For each defence by us, the terrorists will adjust," he said.
The criticisms of Bush's handling of events leading to September 11 could be critically damaging as he enters the presidential race against Senator John Kerry.
His campaign will centre on the premise that his policies and the war against terror have made the US safer.
Bush sought yesterday to deflect Clarke's charges.
"[CIA director] George Tenet briefed me on a daily basis about the terrorism threat to the US," he said. "And had my Administration had any information that terrorists were going to attack New York City on September 11 we would have acted."
Former Defence Secretary William Cohen said the Clinton Administration recognised the dangers posed by al Qaeda and considered the US to be "at war" against the terrorist organisation.
On three occasions after August 1998, US officials considered using missile strikes to kill bin Laden, but each time decided the intelligence wasn't good enough to ensure success, he said.
- INDEPENDENT
Statements to the 9-11 Panel (Sept 23, US time):
Donald Rumsfeld, Secretary of Defence
[PDF]
Herald Feature: The Sept 11 attacks
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