On September 11, 2001, I was in London. I still remember the eerie sense that seized the city of a world turned on its head. Everyone thought London would be hit.
They closed the tall buildings in the Docklands and imposed a no-fly zone over the city. We logged on to the BBC online and waited for an attack to come.
It didn't. At the end of the day we struggled on to the trains and the buses - the longest trip I have taken. London's commuters were even more silent than usual. We willed each other home.
That night we watched the television and saw the planes fly into the buildings. The next day the broadsheets printed special editions with huge double-page spreads showing the havoc in Manhattan. We tried to get on with our work but none of it seemed particularly meaningful. A voice nagged at the back of everyone's minds: When will London be hit?
Over the weeks and months that followed, Londoners tried to silence those voices. It wasn't easy. Every Tube, every public gathering, every landmark was a target. Whenever we were near these things, we felt like targets too.
Two months later I watched the fireworks with friends on Primrose Hill, overlooking Regent's Park. Guy Fawkes Night celebrates the defeat of an attack on parliamentary democracy. That year it held a greater resonance.
Tens of thousands of people gathered. While the sky darkened and we waited for the rockets to be lit, a lumbering jumbo on approach to Heathrow seemed to be flying unusually low and straight for us. It turned away, but the same thought went through everyone's minds. When will London be hit?
Living in London became a calculated risk. Every week an attack seemed inevitable. The newspapers reported how Islamic fundamentalists were manufacturing ricin poison. They told us how the secret service was foiling imminent attack after imminent attack. They explained how the Government planned to close down and evacuate the city in the event of a major terrorist incident.
There was constant talk of dirty bombs, sarin gas and biological weapons. Boarding the Tube, uncomfortable and unpleasant at the best of times, brought on a sense of wall-clinging dread. We felt we were under siege.
The Government told us on the one hand not to be alarmed, but on the other, to be vigilant. Senior officials said it was not a matter of if an attack occurred, but when. A train station evacuated by a security scare became a regular event, and a perfectly acceptable excuse for being late to work.
The locals accepted these events as part of living in London. Some had survived the blitz. Most had seen off the IRA. Everyone had a horror story about something, somewhere that had happened to them on the world's most famous public transport system. Putting up with all of this was just one more thing that had to be done.
But to New Zealanders in London, the attack on New York had a different effect. We weren't used to this. Our thoughts were not "we have to live with this", but "how much more of it can we bear?"
International events did not help. There was a war in Afghanistan. The Government told us that Iraq had biological weapons and was 45 minutes away from using them. The Americans began bombing Baghdad. The silent voices came screaming back. When will London be hit?
In the sweltering summer of 2003, there was a major power outage. The Underground stopped working. Hundreds of thousands of people were stranded on the other side of the city from their homes.
For hours, everyone wondered if this was it. Had the "if" become "when"?
My girlfriend, who worked in the Docklands in the East End, had to find her way home to Maida Vale in the west. Although the outage was not terror-related, for many it was a final straw. Two or three years of waiting for an inevitable terror attack was two or three years too many. We became like so many other New Zealanders and decided we didn't want to live like this. We willed each other home.
Now, tragically but inevitably, the "if" has become "when". London has been hit. It is a small blessing that the attacks were not as bad as they might have been. But that won't diminish the trauma of the victims and it won't reduce the effect on New Zealanders living there.
Thousands of them will decide, like we did, that now is a good time to come home.