With critics questioning the legality of his authorisation of a domestic spying program, Mr Bush used newly declassified details of a previously disclosed plot to show that the threat of terrorism has not abated.
Mr Bush said that in early 2002, the US and its allies thwarted a plot to use bombs hidden in shoes to breach the cockpit door of an airplane and fly it into the tallest building in Los Angeles.
But he named the wrong building. "We believe the intended target was Liberty Tower in Los Angeles, California," Mr Bush said. White House aides later said he meant Library Tower.
The 310-metre-tall Library Tower is now officially known as US Bank Tower but is still referred to by its former name.
Last October, the Bush administration had disclosed the plot to attack targets on the West Coast using hijacked planes, saying this was among 10 disrupted al-Qaeda plots.
Mr Bush said that in October 2001, Khalid Sheikh Mohammed -- the operational mastermind of the September 11 attacks -- had set in motion a plot for another attack inside the US using shoe bombs to hijack an airplane and fly it into the tallest building on the US west coast.
"Rather than use Arab hijackers as he had on September 11, Khalid Sheikh Mohammed sought out young men from South-East Asia whom he believed would not arouse as much suspicion," Mr Bush said.
Mohammed was captured in Pakistan in March 2003 and has since been held at an undisclosed location.
Al-Qaeda leader Osama bin Laden and his deputy Ayman al-Zawahri, believed by US officials to be hiding in the border region of Afghanistan and Pakistan, have so far eluded the US manhunt.
Bali link
Mr Bush said Mohammed conscripted the help of a leader of the al Qaeda-affiliated group Jemaah Islamiyah (JI) in South-East Asia named Hambali, who recruited several operatives with training in Afghanistan.
Hambali, who was later caught, is believed the mastermind of the October 2002 Bali attacks that killed more than 200 people.
"Subsequent debriefings and other intelligence operations made clear the intended target and how Al-Qaeda hoped to execute it. This critical intelligence helped our allies capture the ringleaders and other known operatives who had been recruited for this plot," said the president.
"Their plot was derailed in early 2002 when a South-East Asian nation arrested a key al-Qaeda operative," he said.
Mr Bush said the plot and the way it was thwarted highlights the nature of the global war on terrorism, particularly the importance of robust international cooperation.
Several countries involved
White House counterterrorism adviser Frances Townsend later disclosed a few more details about the plot revealed by Mr Bush.
Ms Townsend said four countries had helped the US thwart the attack: two in south Asia, two in Southeast Asia, however refused to name the countries.
Ms Townsend refused to name the cell members, say where they were arrested or disclose where they were being detained.
Wiretap controversy
Mr Bush has been fighting criticism of his decision to authorise the National Security Agency to eavesdrop without court warrants inside the US on international emails and phone calls placed to and from people with suspected ties to terrorism.
He has said that it was a necessary tool for fighting terrorism and preventing another attack on America.
White House spokesman Scott McClellan denied any linkage between the new details and Bush's aggressive campaign to defend his secret domestic spying program, which some lawmakers have called illegal.
But Mr McClellan said the administration had worked to declassify the new material "probably at least three weeks" right as the controversy over the warrantless surveillance mushroomed.