Within a few hours this week Arlene Foster delivered two pronouncements which illustrate how Brexit has created a new tension between commitment to the Union and commitment to leaving the EU.
Speaking at Policy Exchange in London, the DUP leader said that it was “not a matter for me” whether it is Boris Johnson or Jeremy Hunt who succeeds Theresa May as Prime Minister.
But she went on to say that it was “very important that we leave on the 31 October”. Given that Boris Johnson is the only candidate committing to leave on that date, her comments appeared to be a clear, if coded, endorsement of the front runner in the Tory leadership contest.
That evening, Mrs Foster gave a speech to Finchley Conservative Association in which she stressed that the Union was more important than any other political issue.
Addressing Tories in the seat once held by Margaret Thatcher, Mrs Foster said: “As leader of the Democratic Unionist Party, I have made clear that the protection and promotion of the Union of the United Kingdom is more important than any other political aspiration or cause which we may be focused on at a particular time.
“I would not put forward any cause which I believed would result in a weakening of the Union, but we must always be cautious of how we move forward.”
It was a slightly less explicit restatement of what senior DUP figures from Nigel Dodds down had said in March after being abandoned by Mr Johnson and other Brexiteers such as Jacob Rees-Mogg who voted for the backstop, reneging on their promises.
Mr Dodds said bluntly at the time: “I would stay in the European Union and remain, rather than risk Northern Ireland’s position. That’s how strongly I feel about the Union...the [Brexit] answer must be something that works for the whole of the United Kingdom - that’s our first and main priority.”
The DUP insists that to pit Brexit against the Union is to force an unnecessary choice and that the Union can flourish after the UK leaves the EU.
Thus, Arlene Foster presumably sees no conflict between apparently wanting to see Mr Johnson become Prime Minister while also insisting that the unity of the United Kingdom is far more important than Brexit.
But what if she, and those in the DUP who agree with her, are wrong?
Writing in the News Letter this week, Owen Polley, who for years effectively ran the Conservative Party operation in Northern Ireland, expressed his concerns about Mr Johnson’s loyalty to unionist principles.
Highlighting Mr Johnson’s statement that “we’re allowing the (Northern Irish) tail to wag the dog” on Brexit, Mr Polley said that it “could be read as a chilling warning to unionists about what to expect if there’s a direct choice between delivering Brexit and protecting Ulster’s links to the rest of the UK”.
Mr Polley also highlighted what he saw as weaknesses in Jeremy Hunt’s unionist credentials.
Earlier this month, another Conservative figure with a deep understanding of Northern Ireland politics, ConservativeHome deputy editor Henry Hill, highlighted the difficulty of Mr Johnson even appealing to all of his party members outside England.
Mr Hill told The View that Mr Johnson was “a deeply divisive character; there are a lot of Conservative colleagues who have deep concerns about him, especially in Scotland”.
There have been other straws in the wind which suggest that if Mr Johnson, a populist rather than an ideological politician, enters Downing Street he may be tempted to choose what is best for Brexit rather than what is best for the Union.
Last week, a YouGov poll suggested that most Conservative members believe that leaving the EU is more important than the Union.
And this week the right wing commentator Julia Hartley-Brewer said that “any Tory leadership candidate who puts the Union first has absolutely no intention of delivering Brexit”.
Mr Johnson is publicly insisting on his unionism. But as a political chameleon who has in the DUP’s eyes already betrayed the Union in favour of Brexit, if the party is seen to be backing him and he abandons them again, it is the DUP which will then face the hardest questions.