The election result might have looked like the ideal one for unionism yesterday.
A unionist party props up a UK government, and so has far-reaching influence. Meanwhile, the unionist margin over nationalism widens.
But as thoughtful people in the DUP are aware, they are in a difficult position.
The nation is on the verge of a political crisis, while unionism still faces big challenges. Sinn Fein have been outpolled by the DUP but have even so won a vast number of votes on their ever-upward political journey, as the number of nationalist voters who remember the IRA gets smaller with each election.
Meanwhile, the SNP has suffered a setback but remains by far Scotland’s biggest party.
The DUP risks disaster if it overplays its hand.
Both Arlene Foster’s over-confidence, after her 2016 Stormont successes, and Michelle O’Neill’s display of the same after her own advances in March, antagonised the other community and sent it stampeding to the polls.
Things are so volatile now that another Assembly or Westminster election (or both) is highly possible.
But the DUP not only has now to strike a tone that doesn’t inflame local divisions, which could lead to swift punishment in another election, it has to charm Great Britain.
All yesterday, from the early hours to late evening, commentators were discussing the DUP on national TV and the verdicts were unflattering.
Among the many references that I saw to the party on the BBC coverage were the former Cabinet Secretary Sir Gus O’Donnell, diplomatically describing them “as tricky”, the Green leader Jonathan Bartley denouncing them as climate deniers, and a young man who voted Tory in York but told the presenter that he was unhappy at his party aligning itself with the DUP.
George Osborne’s Evening Standard had on its front page the headline: ‘May’s Irish bail out’. The picture showed her, with an inset image of Nigel Dodds in an Orange sash.
His editorial concluded that a DUP-Tory deal “will mean London taxpayers sending yet more money to Northern Ireland. In this topsy-turvy world, decisions that affect London will be taken in Belfast. That is not a sustainable position; this paper will subject it to close scrutiny.”
The DUP will irritate such influential voices if it demands too much extra money for Northern Ireland, which already gets so much.
Or if the party blocks urgently needed UK-wide fiscal reform amid rising debt such as ending the pensions triple lock or reforming social care.
The Tory Party will be on a permanent election footing now and hard decisions on such issues might never be taken. A sudden election could see DUP influence vanish (along with one or two of its vulnerable seats).
A range of powerful forces are emboldened now that the Tories are so exposed: the House of Lords, the EU, the Liberal Democrats and, most of all, not only the Labour Party but specifically Jeremy Corbyn and his key hardliners such as John McDonnell.
On Wednesday evening I wrote a piece (link below) wondering why pundits were not taking seriously polls that consistently showed Mr Corbyn on 37%+.
The polls were indeed wrong, but not because they over-estimated him (as the experts thought) but rather because they under-estimated his 40% vote share.
This stunning result shows that he could easily win another election. Mr Corbyn as prime minister would not hesitate to force the DUP to choose between a Sinn Fein deal, on republican terms, or joint authority.
Meanwhile, a hard Brexit now looks unlikely. It might even be that, despite the trigger of Article 50, Brexit itself becomes hard to deliver.
Amid all these perils, the DUP would be advised to tread with tact and caution.
Mrs Foster seemed to be aware of that when she talked yesterday of the national interest, not just the local one.
• Ben Lowry (@BenLowry2) is News Letter deputy editor
Ben Lowry June 8: Exit poll at Elmgrove in East Belfast shows huge vote for DUP