Appropriately enough, it all began with a credit union loan. It was 1972 and the North was enduring terrible mayhem, including the killing of 14 innocent people by British soldiers in Derry.
John Hume, a charismatic civil rights leader from Derry, had big ideas about a way out of this murderous mess the country was in. But he had no money.
He and his wife, Pat, had five children and all were entirely dependent on her teacher's salary.
Suddenly, he got an invitation to meet one of the most influential Irish-Americans, Senator Ted Kennedy, at the Irish Embassy in Bonn.
The credit union loan, aptly for a man who had championed the foundation of those people's banks all over Ireland, covered the flight and a hotel room. And happily the meeting was a huge success.
Ted Kennedy believed John Hume had the formula which could unlock the conflict in the North, and he was prepared to use his influence in Washington to put the case to Britain.
The story is well told in the documentary film 'John Hume in America'. The documentary drew in a huge range of characters who were at the heart of it all over almost 40 years.
Contributors included two US presidents, Jimmy Carter and Bill Clinton; two British prime ministers, John Major and Tony Blair; the American mediator George Mitchell and former Taoiseach Bertie Ahern.
There was also a host of former Irish diplomats whose unsung skills proved vital in the whole 30-year-long series of interlinked projects.
John Hume's message was deceptively simple: nothing would be achieved by violence.
The people of Ireland were divided - it was not about two pieces of turf. Resolution must begin in the North and the key to any change was the principle of consent.
In America, promoting this message faced two potent enemies.
One enemy was Irish-Americans' unthinking IRA support, via the "money jar on the bar".
The other, more powerful, enemy was reticence by Washington's political elite, who saw Northern Ireland's problems as an internal UK matter, and not worth offending London by interfering in.
John Hume set out to change the Washington elite's view of Northern Ireland as a more urgent but achievable goal.
Changing grass-roots Irish-America would have to wait.
Relatively quickly he succeeded by persuading not just Ted Kennedy, but a host of others including the legendary Tip O'Neill, as speaker of the House of Representatives, the second most powerful politician in the US.
To paraphrase Hume's long-time colleague, the late Séamus Mallon, John Hume went to where power was and sought to use all his own persuasive powers to influence those with that power. Over a tireless political career, he successfully sold this self-proclaimed "single transferable speech" in Dublin, Washington, London, and Brussels.
Eventually he sold it, albeit very belatedly, to Sinn Féin and the IRA.
There is an interesting contribution in the film from Gerry Adams, who admits they "wasted years". He does not add that they also wasted thousands of lives.
John Hume himself was too ill to take part in the making of that 2018 film. But it is replete with footage of his memorable comments and assessments.
Very striking is his defence of the hugely controversial "Hume-Adams dialogue" in the early 1990s, insisting he was doing it to help save lives and it was no disrespect to IRA victims.
There are many other evocative moments, not least Hume's lament for the dead hunger striker Bobby Sands, whom he saw as a pawn of both British and IRA propaganda.
It was praise indeed to hear the Democratic Unionist Party MP Geoffrey Donaldson admit Hume was light years ahead of unionists in opening up US contacts.
It was also interesting to note that Margaret Thatcher's close ally Lord McAlpine had said the hardline British prime minister lamented ever agreeing the 1985 Anglo Irish Agreement. But she said the Americans had "made her do it".
This film is not all upbeat achievements, though there are uplifting moments.
The grim reality of all the reverses, the senseless killing and destruction, are well chronicled via lots of old footage.
Alongside that is slow political progress.
John Hume worked closely with Dublin, especially with the Irish diplomats.
But he always argued that Dublin governments had never defined what they wanted from Irish unity.
This left unionists to characterise it as "conquest of the North by the south", making unity a dirty word.
"Ireland must be one of the few places on earth where people seriously suggest it is wrong to unite people," Hume reflected.
But for all that, John Hume was no saint.
Séamus Mallon, who died this past January, said he could be a difficult person, bad at accepting criticism, and prone to solo runs which disenchanted colleagues.
Yet Mallon's verdict was unequivocal: "There is a greatness about his political life, what he did, and what he helped to change.
"I would put him in the same breath as Parnell and Daniel O'Connell."