As a historian, I'd be interested to read your answer to the question posed in the title.
Why? Because it was 102 minutes that changed the World.
At 8.46am local time, Flight 11 crashed into the North Tower of the World Trade Center.
At 10.28am local time, the North Tower collapsed.
Those 102 minutes signalled the beginning and the end of a chain of events that have gone down in infamy, and turned the world upside down.
In between, the south Tower had also been struck and had collapsed and the heart of the US Defense - The Pentagon - had also been infiltrated. A 4th plane was grounded by brave citizens before it arrived at its supposed target of the White House or Capitol Hill.
It was that epoch-making, era-defining day in history that heralded in a decade of fear as the Cold War that had ended a decade earlier was now replaced by the War on Terror. The attacks in Bali, Madrid and London were to follow and a whole new level of counter-terrorism legislation the world over would take centre stage.
The war in Afghanistan began barely a month later on October 7th 2001 and continues to this day. Likewise, the second Iraqi War begun on March 20th 2003 and is also still on-going. Thousands of allied and civilian lives lost, billions of pounds squandered. All in the name of security. All with its origins in that fateful blue September day.
Where was I?
September 11th 2001 was a seminal moment and day in history for my generation.
For older generations such as that of my mother, it can be asked 'Where were you when JFK was assassinated?' For those of this modern era, the question asked of us by our children and grandchildren will likely be 'Where were you on 9/11?'
It is scarcely believable that it has been a decade since those horrific pictures of 10 years ago. My memory of that day is still vivid - still etched in detail in my mind.
For us here in the UK, it was early afternoon. The timing of the first impact was 1.46pm BST. I recall sitting alone in my bedroom in the Preseli Hills of north Pembrokeshire at my computer, playing Championship Manager. It was coming to the end of the summer holidays and I was just weeks away from starting my second year in University. I had just turned 19.
By the computer was a TV and I was watching ITV at the time whilst playing on the computer. It was I'm sure, an episode of Crossroads which at about 2pm had gone to the mid-programme interval. But instead of returning to the second half, the transmission was broken by breaking news from ITN.
I vividly remember being taken aback at this break from normality and my immediate thought was 'The Queen Mother has died'. She had just turned 101 and it was only a matter of time and in that split second I recall thinking that that time had come. But no, she would outlive her own daughter Princess Margaret who died on 9th February 2002. Queen Elizabeth passed away on March 30th that same year.
The 21s Century's Pearl Harbour
Suddenly what transpired in front of me on that small TV was an awful accident in New York.
A plane had apparently flown into the North Tower of the World Trade Center. It was a bewildering sight and event to take in. Then came the second impact as the South Tower was hit. Again, such was my utter confusion, I couldn't consider is as anything else than just a horrific coincidence. I don't recall that second impact as clearly as the one that was to follow but that third impact is as clear as day in my mind. When the reports came in that a plane had crashed into the Pentagon, the gravity of the event suddenly struck me in all of its horrific reality.
This, was not an accident. This, was an orchestrated attack on the US mainland, not seen since the attack on Pearl Harbour during WWII.
The rest of the day became a blur from there on in as I no doubt found myself glued to watching the unfolding events.
It was a day of horror that, due to modern technology, was all captured live on camera as it happened. Looking back, it made the event so much more real in the minds of those of us watching it at the time. It wasn't being told that JFK had been assassinated, it was akin to actually seeing the act occur with your own eyes. Here we were, watching this inconceivable act unfold as it happened in real-time.
A New World - A Darker World
I just so happened to be watching a TV at the time that the news broke. Had that not have been the case, the scarring images of the initial impacts would not have lived on with me as they have. But a decade on, the recollection is still fresh in the mind.
It's a haunting feeling. A feeling of a loss of innocence. I had only just began to grow-up having left school to attend University the year before. Here was an added sense that the world in which I now lived was not the one of my childhood. It was a much darker, scarier world. Over the past 10 years, it has remained thus.
Where were you?
So where were you on September 11th 2001? As a piece of social and oral history, I'd be interested to hear your remembrances of this tragic day, 10 years on.