On his Twitter account last Thursday night, Richard Haass described Nelson Mandela as "a great man". And the US diplomat also commented on South Africa's "great fortune that he had a partner in FW de Klerk". "Neither alone could have effected peaceful change," Dr Haass wrote.
And he also commented that the Belfast/Good Friday Accord here had shown "what leaders willing/able to compromise can achieve".
As he wrote, the news in Northern Ireland was not just remembering Mandela, but reporting on a dissident republican gun attack on police; an ugly reminder of an unfinished and incomplete peace.
Today, Haass, with talks vice-chair Dr Meghan O'Sullivan, begins a two-week intense negotiation with the Executive parties. Their talks are about other elements of that imperfect peace: flags, parades and the past.
And, before a Christmas deadline, the US talks team hopes to make proposals that will represent "meaningful progress" on all three issues.
We know some of what Haass and O'Sullivan are exploring inside the talks room. It was contained in questions sent to the parties before the negotiations begin in earnest today.
On existing processes addressing the past, Haass asked how they might be "reformed, combined or improved". And there was another interesting question reported by this newspaper last week: "What might a process to design and validate a new Northern Ireland flag look like?"
"Progress is painstakingly slow," Ulster Unionist negotiator Tom Elliott told the Belfast Telegraph. "I've always warned people to be cautious about what is achievable and I would still hold to that."
Elliott accepts that the next two weeks will make, or break, these negotiations. And he is prepared to discuss what is "out" as far as his party is concerned.
"An amnesty is out," he said. "A truth commission is out – certainly as Sinn Fein would see it. And any replacement of the Union flag as our national symbol is out."
Haass and O'Sullivan will need the mood and the compromises of the Good Friday negotiations 15 years ago if they are to get business done. And that means the will and muscle to lift three of the heaviest issues out of the political mud.
"The challenge is recognising that this is now the best opportunity to comprehensively address the past," another of the talks negotiators, the SDLP's Alex Attwood, said.
He said the moment should not be squandered and that not just the parties, but "crucially the governments", should "seize this chance".
But the governments – Irish and British – are not at the Haass table and both have major contributions to make to any exploration, or excavation, of the past; major contributions in terms of shaping such a process and participation within it. They are not onlookers.
So, how can Haass, within a two-week timeframe and deadline, realistically expect to reach to those heights? "In light of the Smithwick report [into the IRA ambush and murder of police officers Harry Breen and Bob Buchanan], we are clear that any process to deal with the legacy of our troubled past must not put short-term political expediency before the need to have an effective process that offers the victims the opportunity to pursue truth and justice," talks negotiator Jeffrey Donaldson said.
"Our main concern, at this stage, is whether the time remaining will be sufficient to enable us to arrive at a comprehensive understanding," the DUP MP added. "However, we recognise that it is essential that progress is made."
And another negotiator, Naomi Long, believes the challenge to make progress is being encouraged from outside the talks room and the political frame.
"The big challenge is for us to deliver on the expectations of the public ... people want an ambitious and a progressive outcome which will unlock these very difficult and sensitive issues," the Alliance MP said. "It's up to us in this process to deliver for those people."
Somewhat controversially, the Sinn Fein negotiating team published its submissions to the Haass process, documents that allow us to see the gaps that exist within this negotiation and the middle ground that has to be found.
Take just one issue, that of flags. The republican position is defined within the policy frame of "equality, or neutrality". "This can translate into both national flags on display, or no flags at all to be flown," one of its documents states.
Unionists won't buy into that – and Sinn Fein will not support the idea of the Union flag on all councils on designated days with Belfast given special status 365 days a year.
So, this explains the exploration of a 'new', or 'neutral', flag. It also highlights the scale of the challenge.
To go back to what Haass said about Mandela and de Klerk, this will only work in partnership approaches; and it will only work if a Good Friday mood can be found.
And there are empty seats at this talks table.
Do the governments – Irish and British – really want to address the past? Or is it still being avoided?
Do the parties want an approach that moves things forward? Or is the past still a plaything and a battlefield on which some still hope to win?
Two weeks – however intense the negotiations – is not enough time. Beyond Haass, whatever his proposals and recommendations, there will be more questions that will need more time.