Image source, ReutersImage caption, US President Donald Trump is visiting Ireland
When another world leader meets US President Donald Trump the only certainty about what might happen is the uncertainty about what might happen.
This was exactly the case ahead of President Trump's two-day visit to Ireland.
Nobody could have predicted that by the end of the first day, the main global headline would be his desire to see a unified Ireland.
As the shockwaves of his remarks rippled through this island and Great Britain, it was unclear whether this represented a new US administration policy, or an off-the-cuff remark from a president who likes to take questions from reporters, and likes to give answers.
Image source, ReutersImage caption, President Trump with the Taoiseach (Irish Prime Minister) Micheál Martin
Former Republican Congressman Mick Mulvaney was Trump's special envoy to Northern Ireland in his first term in office.
He cautioned against anyone reading too much into the president's remarks.
"This does not represent a shift in US foreign policy," he said.
"We're still very much committed to the Good Friday Agreement."
"There is bipartisan support for that deal, and that is not going to change."
Although both agreed that Donald Trump was probably right to say that "eventually" unification would happen, that did not mean the US was about to start pushing for it.
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Watch: President Trump says he would 'love' to see Ireland unified
Giving an answer to a question that is asked at a free-flowing press conference is one thing, but Donald Trump repeated his sentiments a short time later when he was delivering a speech to an invited audience at the US Ambassador's residence.
In fact it was almost the first thing he mentioned, hinting that maybe he realised he had kicked over a can of worms at his earlier appearance.
The rest of that speech was curious. It was billed as a 20-minute address to Irish and Irish American business leaders, but was about twice that and strayed largely into domestic US matters.
President Trump has a speaking style that he describes himself as "the weave".
He can bounce from topic to topic during any speaking engagement, veering off the script and then returning to the matter at hand.
Today he lauded his own achievements, as he sees them, such as clamping down on illegal immigration, doing deals and boosting defence production.
He repeated his criticisms once again of what he views as the UK's lack of support for his military operation in Iran.
Image source, ReutersImage caption, Donald Trump meets Irish President Catherine Connolly
But who was his target audience? The gathered business leaders in Dublin or a US audience tuning in before it was even dawn in much of that country?
This November's crunch midterm elections are fast approaching and the Republican party is under intense pressure because of the president's policies.
They may lose control of one or both houses of Congress.
About one tenth of the US population claim Irish heritage but they are not a homogeneous voting bloc.
Was he trying to target Irish-American independent or swing voters in the US, of which there are many who have flip-flopped between the Republican and Democratic party in recent years?
Some of them do support a unified Ireland and so in this time of chasing every vote, perhaps that played a part.
Bill Clinton secured a lot of Irish-American support when he was running for president, by promising to get engaged in the peace process.
They voted for him and he followed through on his promise and much of that work led to the foundations of the Good Friday Agreement.
But, Irish America is a different place now. Indeed, America is a different place now as politics have become more polarised.
The November election campaigns show no indication that will change anytime soon.
But political leaders in Ireland will be hoping the only debate tomorrow is about the play on the golf course.
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