As a South African, whose parents were not allowed to speak to each other under a banning order by the apartheid regime, Mr Hain had first-hand experience of how difficult it can be to finally settle a conflict.
He said he told the Cabinet: "Nelson Mandela came out of prison in February 1990 and four years later in April 1994 he was President. People look back on that and think that was a miracle, and it was, in its own way. What people forget is that more people were killed in that four-year period of South Africa's history than at any other time."
He added: "I make that point not to say I am expecting violence and death in Northern Ireland. On the contrary I think that is behind us. But I do think it illustrates the point that when you are closest to a final agreement is when it is hardest. You may be closer but it's terribly difficult for people to take the final step. But I think we will get there; I am optimistic. The march of history is with a successful democratic conclusion to this process."
We were sitting in Mr Hain's office at Millbank in central London as Tony Blair welcomed the IRA statement live on Sky News. Mr Hain watched silently from his desk, showing no sign of envy that Mr Blair was taking all the limelight. Did he feel, in Mr Blair's words, the "hand of history" on his shoulder, I wondered?
"No,'' he said. "There have been so many who have gone before me, it would both be presumptuous and a bit gratuitous to say that's the case.
"It goes back a long way, Tony Blair's courage and vision in getting to the Good Friday Agreement which no Conservative Prime Minister had been able to do in 20 years. He broke the mould over the way Northern Ireland had been handled by previous Prime Ministers."
He says John Major negotiated the Downing Street Declaration and Margaret Thatcher, however reluctantly, secured the Anglo-Irish Agreement, but Mr Hain said: "Under Tony it was a quantum leap in thinking and understanding how to resolve this matter."
Jonathan Powell, Mr Blair's chief of staff, played a "pivotal role: as a go-between," but Mr Hain added: "Paul Murphy, my predecessor, is the unsung hero of this process both as Mo Mowlam's deputy and then as Secretary of State. I find everybody wherever I go people pay tribute to what he did."
Mr Hain has not dealt directly with the IRA, he said. His contacts since arriving in the job three months ago have been Gerry Adams, Gerry Kelly and Martin McGuinness. "That's been the basis on which I have negotiated this. There have been almost daily meetings," he said.
The final pieces of the jigsaw fell into place after five hours of talks with Mr Adams in Hillsborough Castle. He would not say what they discussed, but he did not deny it included the freeing of the IRA bomber, Sean Kelly, whom he had put back into prison only six weeks before for breaching his licence for release.
That decision outraged some Unionists and stuck in the craw of some of his ministerial colleagues. In the autumn, Mr Hain will introduce legislation which will, among other things, provide an amnesty for the IRA men who have been on the run for years, so they can returnwithout fear of arrest. But, in the end, it will be for Ian Paisley and Mr Adams to do the deal, and that is the hard part. Mr Hain thinks the real finger of history is pointing at the unlikely figure of the ageing firebrand of the DUP .
"I like him as a person because he's a man of destiny in Northern Ireland terms," he said. "We have not agreed with each other in the past and will still have disagreements today. He is now the leading figure in Northern Ireland politics and his role is going to be crucial. Ian Paisley has it in his hands to become the first minister of a reconstituted Northern Ireland executive and assembly in the best circumstances for any unionist leader to do this, which is with IRA activity shut down. There is a long way to go to achieve that. We still have to get a political settlement. There are going to be many months of heavy lifting."
It is one of the great ironies that peace may now be secured when Ulster politics has become so polarised. Sinn Fein and Mr Paisley's DUP gained seats and the more moderate Ulster Unionist leader, David Trimble, with whom Mr Blair did business, lost his seat and has been deposed. But Mr Hain believes that may have helped to create the conditions for a deal.
"My South African experience is relevant here," he said. "First, in the end the deal there was done between the two most polarised parties, the Afrikaaner ruling apartheid elite and the ANC cadres of Nelson Mandela whom they'd locked up, killed and smashed over many decades of apartheid. They did the deal.
"Provided events sustain this, I think Ian Paisley and his team have the leadership capabilities to negotiate the ending with all the other parties, Sinn Fein included, because there is nobody either side of them to really speak of, a handful of dissident republicans that don't count for anything, but nobody to really speak of. If you can get them round the table, you are in the business of striking a deal."
He does not rule out last week's announcement leading to a united Ireland. "I don't see that changing for the foreseeable future, but who knows after that? The great virtue of the Good Friday Agreement and its endorsement by referendums on both sides of the border is that the people have spoken, and the politicians have to listen, whether they are unionist or republican, nationalist or alliance."
Next door to the Northern Ireland Office on Millbank is the MI5 headquarters. The lights have also been burning late there recently in dealing with the new generation of home-grown bombers who have replaced the IRA with a summer campaign of terror in London. I asked Mr Hain whether the lesson to be learned from reaching an end to IRA violence meant you had to address the concerns of the terrorists committing bombings in the name of Islam?
Mr Hain began with the stock ministerial answer, saying there were no parallels between the IRA and the Islamic fundamentalists. But he has a reputation for being free-thinking, which has got him into trouble in the past with Downing Street and, while stressing that terrorism had to be ruthlessly blocked, he added: "You have to deal with any of the conditions that produce it."
That included, he said, bringing peace to Iraq. "Nobody suggests the conditions in Northern Ireland were optimal or ideal for anybody. They are now completely different. That has been part of the process of removing any of the spurious justification for terrorism in Northern Ireland. In the situation of Islamic terrorism, what we have to do is pursue - as we are - a series of international agendas for justice and human rights, a settlement of the dispute between Palestinians and Israelis, a peaceful, democratic Iraq, a peaceful, democratic Afghanistan, and conquering world poverty, which is what the G8 was all about."
He quickly added: "But you are dealing here in the case of Osama bin Laden and his derivatives with something that you cannot negotiate with, because it has no clear political agenda other than to impose a brand of fanatical dictatorship which would roll the world back centuries, oppress women, shackle and put human rights into a concrete bunker and dispense with it. You can't negotiate with that."
I said I had read a piece by Jonathan Freedland saying Ken Livingstone, the Labour London Mayor, was playing with fire by suggesting Palestinian suicide bombers were different because they could fight back only with their bodies.
"I don't agree with Ken," said Mr Hain. "Terrorism is terrorism whether it was IRA terrorism in Belfast or Islamic fundamentalists in London. The idea that Palestinian terrorists are justified is just out of court."
He admits some IRA men will not give up the armed struggle, and may join the Real or Continuity IRA, but he does not think many will do that. He said: "The whole context in which terrorism now operates has changed things fundamentally."
* BORN: Nairobi 1950, raised in South Africa
* EDUCATION: Queen Mary, London; Sussex University
* CAREER: 1969: Chaired the campaign to stop cricket tour of South Africa
1971: Chair of Young Liberals
1976: Union of Communication Workers
1991: Elected MP for Neath
1997: Junior minister at Welsh Office
1999: Minister of state, Foreign Office
2001: Energy minister; minister for Europe
2002: Secretary of State for Wales
2003: Leader of the Commons
2005: Secretary of State for Northern IrelandReuse content