This weekend marks the tenth anniversary of the September 11th attacks.
I was the UK Ambassador to the European Union in Brussels at the time, and saw firsthand Europe's reaction - one of sympathy for, and unity with, the United States. The French newspaper Le Monde's headline captured the mood perfectly: "Nous sommes tous Americains"; "We are all Americans". In the UK, at the changing of the guard at Buckingham Palace the military band played the Star Spangled Banner in a simple but powerful symbol of our transatlantic solidarity.
The display of solidarity came not just because of our long-standing alliance. Sixty-seven Britons died that day; more than in any single terrorist attack before or since. Like the American victims, they represented the whole spectrum of British society, old and young, from all walks of life. They are missed and will never be forgotten. Her Majesty The Queen visited the British Memorial Garden in New York last year - a haven for quiet reflection amid the bustle of the financial district.
While we shared in the pain of the attacks, we also watched with admiration the US's determined process of recovery. Doctors, nurses, paramedics, police and fire fighters from across the US travelled to New York and Washington to help the first responders there. Ordinary citizens got involved. The response showed national character and resolve, and also will not be forgotten. A similar sense of national resilience was shown in Britain after the attack on the London transport system in July 2005.
Ten years on, Britain and America have fought together in Iraq and Afghanistan, cooperated against terrorism around the world, and most recently acted together to help the people of Libya free themselves from repression.
It has been a hard decade, at home and overseas, and one of sacrifice of too many lives. But the 9/11 generation of soldiers, intelligence experts, civilian peace-makers and builders of better societies have learned from their experiences. Joe Klein recently had a cover story in Time Magazine branding this the "new greatest generation" of leaders, hardened in battle, but prepared for the global challenges of the post 9/11 world.
The international community has had its moments of division and incoherence over the past decade. But on Sunday the rest of the world will once again stand united with America, painfully aware of our shared losses that September day and in the conflicts which followed, but determined to build on the hard-won gains of the last decade to create a better and more prosperous world in the years to come.
Follow Nigel Sheinwald on Twitter: www.twitter.com/UKinUSA