Arlene Foster and Nigel Dodds looked delighted as they walked up Downing Street yesterday, and no wonder.
Think about the position they now find themselves in.
Mrs Foster seemed, for a few wobbly days after the March Assembly elections, to be doomed as DUP leader. She was widely blamed for the poor result not only of her party, but of unionism (which lost its majority), by antagonising nationalists and presiding over the RHI fiasco.
Nigel Dodds must also have feared a few weeks ago that he was finished politically. John Finucane was a strong republican challenger in a seat perhaps fractionally more nationalist than unionist.
But now Mr Dodds is confirmed in his North Belfast seat with a decisive, albeit slim, majority over Sinn Fein. He is the deputy leader of a party at Westminster that holds the balance of power.
Mr Dodds is well known in the House of Commons, and as a man who holds a first-class law degree from Cambridge, respected by some of the most powerful people in the land.
Mrs Foster leads a party that surged an astonishing 10% in its vote share, taking it from being 1,100 votes ahead of Sinn Fein to 55,000 votes clear. That is despite the republicans having had their best ever vote.
Mrs Foster leads a party that the Conservatives must woo to hold on to power, which they so urgently want to do.
Given this set of circumstances, the DUP are of course beaming with joy, but they need to be nervous as hell too.
This is a deeply uncertain time for unionists. The new found influence could vanish.
The Tories could go a number of ways. They could shore up Mrs May, who performed well in the House of Commons yesterday and reportedly even better in front of her MPs the previous evening, at Tory MPs’ 1922 Committee.
Or they could select a new leader such as Boris Johnson, and if polling goes well gamble on a general election.
In the former situation, attrition from a few by-election losses or key rebellions by emboldened anti Brexit Tory MPs (who decide that Remain is more important than party) could force a poll.
In either scenario, if recent experience of Western democracies has taught us anything at all, it is that an election could go any way (easily resulting in Corbyn in Downing St).
Arlene Foster talked on Saturday about the Union being the DUP’s guiding star. It was a nice turn of phrase and reassuring to unionists.
That might set their ultimate co-ordinate, but the lesser star they should follow just now is the one that avoids at all costs another election. It is possible – just possible – that informal Tory deal will bed down and be successful for a few years (but if so, Brexiteer unionists should note that it will probably be on the basis of a soft Brexit that commands cross-party support).
Of course the DUP can make demands, but only some (I will write this week on why I think legacy is one).
A range of disastrous scenarios could emerge quickly, as Sinn Fein – cleverly mimicking the DUP yesterday at Westminster – well knows.
Some of the points above I already made in a column I penned on Sunday night. But the position for the DUP has worsened since then, in that the scale of the loathing of them has become clear, even among some Tory supporters. Much of it is grotesquely ill-informed but it is the base from which the DUP has to work.
Changing the perception might not even be possible. It certainly won’t be easy.
But trying to alter it, by surprising people and displaying their Britishness and speaking modestly, must be one of their highest priorities.
The future of the Union might depend on it.
• Ben Lowry (@BenLowry2) is News Letter deputy editor
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