The US Central Intelligence Agency has released 71 presidential intelligence briefs detailing warnings about Osama bin Laden and Al-Qaeda in the years leading up to the September 11, 2001 attacks.
The release came on Friday as the United States marked the 25th anniversary of the terrorist attacks that killed nearly 3,000 people.
The documents, covering the administrations of former Presidents Bill Clinton and George W. Bush, reveal how intelligence analysts tracked the growing threat posed by bin Laden and his network before the attacks.
Among the most striking warnings is a September 10, 1998 brief, which said Al-Qaeda might “fly an explosive-packed airplane into a US city”.
Another briefing dated December 4, 1998, warned that bin Laden and his allies were preparing attacks in the United States, including a possible aircraft hijacking.
The documents also show that US intelligence had identified bin Laden as an increasing threat to the American homeland years before the attacks.
However, the intelligence available to officials was often incomplete, uncertain and lacking crucial operational details.
The release offers further insight into the challenges faced by US intelligence agencies as they attempted to understand Al-Qaeda’s plans and warn senior policymakers.
The 9/11 attacks occurred on September 11, 2001, when 19 Al-Qaeda operatives hijacked four commercial aircraft.
Two of the planes were flown into the World Trade Center’s Twin Towers in New York, causing the skyscrapers to collapse.
A third aircraft struck the Pentagon in Arlington, Virginia, while the fourth crashed near Shanksville, Pennsylvania, after passengers attempted to take control of the plane.
The attacks prompted the United States to launch its “War on Terror”, beginning with military action against the Taliban and Al-Qaeda in Afghanistan.
The US later invaded Iraq in 2003, although Iraq’s government was not responsible for the September 11 attacks.
The intelligence warnings have remained a subject of intense scrutiny in the years since 9/11, particularly over whether the information available to different agencies was properly shared and acted upon.
The 9/11 Commission found that American intelligence agencies had received repeated warnings about bin Laden’s intentions and possible attacks in the United States. But officials did not have sufficient information to determine exactly when, where or how the September 11 operation would occur.
The newly released briefs provide additional historical detail about those warnings and the evolution of the US government’s understanding of Al-Qaeda before the attacks.
