Rory Hanrahan was speaking yesterday after an Irish diplomat attended the service to his late father Sean O’Callaghan, who died last August at the age of 62.
The event to celebrate and give thanksgiving was held at St Martin in the Fields church in Trafalgar Square in the centre of London.
After the service, Mr Hanrahan welcomed the fact that Gerald Angley from the Irish Embassy to the United Kingdom had been present.
He said: “I felt that both the British and the Northern Irish establishment did honour to the duty and service that my father did to this nation, to both nation states, both these islands, and the Irish embassy finally acknowledged, the Irish government, after 21 years the service and sacrifice he made on behalf of the Irish nation and peace on these islands.”
O’Callaghan rose to become senior in the IRA in the Republic of Ireland in the late 1970s and early 1980s, but after the deep remorse he felt about murdering two people in Northern Ireland — a female soldier in the UDR and a Catholic male RUC officer — he began to work as a garda agent.
Later he handed himself into police in England and confessed the murders.
He would become of the IRA’s most devastating critics.
The service in London yesterday morning was attended by relatives, politicians, commentators, security force personnel, statesmen and admirers from both sides of the Irish Sea, including the former first ministers Arlene Foster and Lord Trimble.
Lord Trimble gave a Bible reading from the New Testament, while one of the one-time Ulster Unionist leader’s former advisors, Lord Bew, read a passage from Shakespeare’s play Othello.
The Conservative peer Lord Salisbury gave an address, as did the writer Douglas Murray. A further address was given by the think-tank leader Dean Godson.
The commentator Ruth Dudley Edwards read from Sean O’Callaghan’s book about James Connolly.
The Queen’s University lecturer Liam Kennedy, who originally comes from the Republic of Ireland, spoke about O’Callaghan as an “Irish exile”.
O’Callaghan’s brother Donie read a letter from their sister, and also gave a reading of ‘Epic’ by the Irish poet Patrick Kavanagh.
The congregation included the security and former Northern Ireland Office minister Ben Wallace MP, the former military leader Colonel Tim Collins, the ex Ulster Unionist MP David Burnside, the economist Graham Gudgin and the Presbyterian minister Rev Brian Kennaway.
The former editors of the Daily and Sunday Telegraphs, Charles Moore and Dominic Lawson, came to pay their respects.
There was a retiring collection for “four causes that were close to Sean’s heart”: Art Against Knives, RUC and UDR benevolent funds, and the Trenchtown Reading Centre in Jamaica.
Aileen Quinton, whose mother was murdered by the IRA in Enniskillen, also attended the service.
She said: “I visited Sean when he was still in prison. I think his motives were complex and for me ultimately unfathomable. However he was unequivocal about his renunciation of terrorism and how it was not justified. That is what I came to celebrate.”
Outside the service, Ms Dudley Edwards told the News Letter that O’Callaghan was “the most extraordinary political analyst”.
She added: “He was a bit like a Kremlinologist. There was a policeman here and he said that when he read Sean’s The Informer he understood what he was dealing with.”
She added: “He broke a taboo, no-one tells the truth about their time in the IRA. They’ve either been heroes or they’re in denial.
“And what Sean did is extraordinarily rare. He did some terrible things, he murdered two people, he robbed, he blew things up but he then confronted what he had done, accepted what he had done, realised he was in a sectarian war and not a war of freedom fighters and faced it and said what do I do now?
“He could have just melted away, he was only 20.”
• Further reports from the service in Friday’s paper