INTERNATIONAL: Thousands of people will gather in New York City, Washington D.C., and Shanksville, Pennsylvania on Saturday to mark the 20th anniversary of the 9/11 attacks. Almost 3,000 people were killed when hijacked passenger jets were flown into New York’s twin towers and the Pentagon. A third was brought down in a field in Pennsylvania by its passengers. It’s intended target had been Capitol Hill. It was almost 90-minutes of terror that has changed the world we live in…

Tuesday, 11 September 2001 at 8.47am. The North Tower of New York’s World Trade Center already ablaze, in what most people thought had been a terrible accident. American Airlines Flight 11 had flown into it at 8.46 in the morning, local time. All thoughts of an accident evaporated at 9.03am, when the South Tower was hit by United Airlines Flight 175. It was then that the world knew the United States was under attack.

34 minutes later, at 9.37am, American Airlines flight 77 hit the Pentagon. At 9.59am, back in New York, the unthinkable – the South Tower collapsed. A few minutes later – reports of the crash of United Airlines flight 93 in a field outside the town of Shanksville, Pennsylvania. Over in New York, at 10.28am, the unimaginable – the North Tower collapsed as well. It was then that everyone watching knew the world had changed.

A subsequent investigation revealed that United flight 93 had been downed by passengers on hearing that the hijacker’s intended target had been the US Capitol. Those in the plane all knew what had happened in New York and Virginia.

Osama bin Laden – the leader of the Al Qaeda network – was quick to claim responsibility. He was being harboured in Afghanistan by the Taliban. While the FBI launched its investigation into what would become called “a spectacular failure of imagination” on the part of US security agencies, The White House of George W. Bush launched its “War on Terror”.

A US-led coalition stormed into Afghanistan, with the phrase “collateral damage” quickly entering everyday English. Thousands of men, women and children killed, all in the relentless pursuit of one man, but just three months later, then-US President George W. Bush made this statement:

"Thanks to our military and our allies and the brave fighters of Afghanistan, the Taliban regime is coming to an end."

He was right – at least at the time, but Osama bin Laden would continue to haunt the US for a further 10 years. It wasn’t until April 2011 that he was killed in a raid by US marines in the small Pakistan town of Abbottabad, while an anxious White House watched.

Back in Afghanistan, there was a US-backed democratically-elected government and signs life was settling down once again, but thousands of foreign troops were keeping the peace. Questions started to be asked about just how much longer they’d need to be there. Then-President Barack Obama dropped into visit troops at Bagram Air Base, pledging to end the war:

"For many of you this will be your last tour in Afghanistan. And by the end of this year, the transition will be complete and Afghans will take full responsibility for their security and our combat mission will be over. America's war in Afghanistan will come to a responsible end."

But it didn’t. A full seven years later, almost 20 years after the 9/11 attacks, a shambolic US troop withdrawal put the Taliban right back where they were. This time though, they’re promising to rebuild, as well as respect human rights within the framework of Islamic law. The world watches and waits to see if they keep those promises.

While 20 years of war effectively achieved very little, the 9/11 attacks did indeed change the world, with a rise in terror groups and a shift in the global balance of power, but most fundamentally, it changed the way we travel. Airports have since adopted their own new-normal, with pre-flight screening and seemingly never-ending security checks, with passengers needing to remove belts and shoes, wristwatches and mobile phones.

20 years on, we all still remember where we were the moment we heard about what was happening in New York that September morning. It is a day the world will simply never forget.

^{Photo: SMOKE BILLOWING FROM NORTH TOWER AS PLANE HITS SOUTH TOWER VARIOUS OF COLLAPSED WORLD TRADE CENTER}