On a warm, cloudless Tuesday morning in September 2001, the United States suffered the deadliest terrorist attack in its history, changing the world forever.
At 8.46 am, American Airlines Flight 11, a Boeing 767-200ER carrying 92 people, struck the North Tower of the World Trade Center between floors 93 and 97.
The floors were occupied by Marsh McLennan, and all 358 people present in the company’s offices that day died, alongside everyone aboard the aircraft.
Those trapped on the 13 floors above the impact burned alive, asphyxiated, or choked, while 200 others jumped from the tower knowing the fall was unsurvivable.
It had already surpassed the death toll of 168 killed when anti-government extremists left a truck bomb outside a federal building in Oklahoma City in 1995.
At first, the chaos seemed like a terrible accident, the kind of nightmare that had always shadowed a world of skyscrapers and commercial aviation.
That illusion lasted just 17 minutes before United Airlines Flight 175 from Boston to Los Angeles approached Manhattan far too low and smashed into the south face of the South Tower.
Broadcast live on television to a global audience, the second impact made the terrible truth undeniable: these were deliberate, coordinated, merciless attacks on America’s biggest city.
Three minutes before impact, passenger Peter Hanson called his father in Connecticut using an Airfone, his final words among the most chilling recorded that morning.
“I don’t think the pilot is flying the plane. I think we are going down. I think they intend to go to Chicago or someplace and fly into a building. Don’t worry, Dad. If it happens, it’ll be very fast… Oh, my God… oh, my God, oh, my God.”
Flight 175 struck the South Tower at 587 mph, carrying 34,000 litres of aviation fuel, killing all 65 people aboard instantly and trapping more than 600 people above the 77th floor.
President George W. Bush was visiting an elementary school in Florida when his chief of staff, Andrew Card, leaned in and whispered the words that defined a presidency.
“A second plane hit the second tower. America is under attack.”
At 9.37 am, an American Airlines Boeing 757 smashed into the west side of the Pentagon in Virginia, killing all 64 aboard and causing 125 further fatalities inside the building itself.
Secretary of Defense Donald Rumsfeld, then 69 years old, left his office, walked to the impact site, and helped tend to the injured in the immediate aftermath of the strike.
At 9.59 am, the South Tower collapsed, its sagging floors pulling on weakened perimeter columns until the uppermost stories dropped vertically to the ground in an unstoppable cascade.
United Airlines Flight 93 had been hijacked at 9.28 am, and its passengers, aware of what had happened to the other planes, resolved to act before it reached its target.
Passenger Tom Burnett, a 38-year-old businessman from California, ended his final call to his wife with the words, “Don’t worry, we’re going to do something.”
Another passenger, Todd Beamer, spoke with Airfone operator Lisa Jefferson before she heard muffled voices and then his reply: “Are you ready? OK. Let’s roll.”
The cockpit voice recorder captured the sound of a food cart ramming the cockpit door before the aircraft crashed at 10.03 am in a field in Stonycreek, Pennsylvania, just 20 minutes’ flying time from the US Capitol.
At 10.28 am, the North Tower collapsed, and the final death toll from the attacks reached 2,977 people from at least 102 countries, with as many as 25,000 injured.
By 9.30 pm that evening, CIA director George Tenet had confirmed to the President that al-Qaeda, the Islamist terrorist organisation led by Osama bin Laden, was responsible for the attacks.
On 14 September, President Bush stood atop the debris at Ground Zero and spoke through a bullhorn to first responders gathered at the site.
“I can hear you. The rest of the world hears you. And the people who knocked these buildings down will hear all of us soon.”
Bush declared a Global War on Terror in which, as he stated plainly, “Either you are with us, or you are with the terrorists,” reshaping American foreign policy and global geopolitics for a generation.
No new technology, no new resources, and no new opportunity had enabled al-Qaeda’s plan, as commercial jet aircraft had existed since 1952 and skyscrapers since 1885.
What was new, as historians have since observed, was imagination: the evil genius to weaponise the utterly ordinary and inflict a wound that has never fully healed.
By the measure Bush himself set, that the war would not end until every terrorist group of global reach had been found, stopped and defeated, the conflict that began that morning continues still.