Psychologists call it a flashbulb memory, a moment in time remembered vividly seared into the consciousness. For millions of French the events of 15 April 2019 will be recalled forever like yesterday.
On the banks of the Seine that evening we filmed the Notre-Dame on fire as thousands of Parisians stood shoulder to shoulder in hushed silence.
That memory is as vivid as the moment the great spire of the cathedral came crashing down, plummeting in flames through the roof of the building as hundreds of horrified onlookers gasped.
“We have come to stand in solidarity with an old friend,” one man told me that evening in tears, his young child on his shoulders.
There were so many people out doing the same and the atmosphere was deeply moving.
There was a deeply sad, reverential quiet as the entire city seemed to come to a halt in respect for its much-loved building
File pic: Reuters
That night, in front of the ruins of the cathedral, French President Emmanuel Macron vowed to rebuild it “even more beautifully”.
His ambition seemed as vaulting as the flying buttresses the building is famous for. Within five years seemed impossibly optimistic.
But the people of France and admirers far beyond rose to the challenge.
Children emptied piggy banks, pensioners donated precious savings, and multinationals donated millions. The bulk of the €850m (£705m) given by 340,000 people was pledged in the days after the disaster.
The money allowed an army a thousand strong to get to work, to restore the cathedral to its former glory, in painstaking fidelity to its original design.
More than 1,000 oak trees have been felled to rebuild the roof, known as the forest, that was so comprehensively destroyed.
Read more:
First glimpse inside restored Notre-Dame cathedral
The restoration of the heart of France
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Glimpse inside restored Notre-Dame
Chance for embattled Macron to salvage his presidency
The reopening ceremony will be a moment of huge pride for France but also an opportunity for its president.
Among the heads of state and dignitaries he has invited America’s next leader.
Five years after his address in front of the cathedral’s smoking remains, Mr Macron stands today in the smouldering ashes of what remains of his presidency.
The political crisis engulfing him deepened again this week as he lost his fifth prime minister.
He will use the day to project French soft power and to flatter Donald Trump just as he did a few months into the president-elect’s first term in office on Bastille Day in 2017.
Mr Macron is also inviting Ukrainian President Volodymyr Zelenskyy.
It is unclear if the two guests will meet but they may do so in passing at least.
The French leader, like his Western allies, is keen to forge a consensus on Ukraine ahead of the second Trump administration.
They are concerned Mr Trump will enforce negotiations between Ukraine and Russia that could reward Russian President Vladimir Putin for his aggression.
Creative diplomacy will be vital in the months ahead. Mr Macron hopes to make a start today.