The DUPs MPs have become increasingly forthright about what Theresa May should do

That has been influenced by two developments – Theresa May bringing the DUP back into the fold after the party contributed to the Commons mauling of her proposed deal a fortnight ago and a logical contradiction which has opened up in the EU position.

For all of its history the DUP has been aggressive in how it does politics. From its founder Ian Paisley being pictured with a sledgehammer and the slogan ‘smash Sinn Féin’ to deputy leader Peter Robinson leading an ‘invasion’ of the border town of Clontibret in the 1980s to Ian Paisley Jr repeatedly shouting “moo, moo, moo” as a member of the Women’s Coalition spoke in the 1990s, the DUP has always been far less concerned about the niceties of politics than most of its rivals.

That willingness to act beyond the normal constraints of political discourse has been one of the secrets of the DUP’s ability to extract significant concessions during negotiations - most obviously in 2017 when the party secured a minimum of £1 billion in new money for Northern Ireland in order to prop up Theresa May’s government.

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Even when in a weak position, the party believes that attack is the best form of defence.

Over the last year there has been open DUP frustration – reaching a crescendo in December – at what it saw as Mrs May’s far less robust style of negotiation.

But that simmering discontent has come to the fore over the last week as the DUP saw what it viewed as an open goal from the EU side.

Last week – in what was the most difficult week for the otherwise watertight Dublin-Brussels relationship since the talks began – the European Commission’s chief spokesman said that in the event of a no deal Brexit it is “pretty obvious you will have a hard border” in Ireland.

Dublin dismissed that argument, with Taoiseach Leo Varadkar stating that “even in a no deal, there will not be a return to a border”.

The very obvious question from the DUP was: If a hard border is not going to happen under any scenario – even a no-deal Brexit – why is the EU unprepared to move on the backstop, when it is supposedly there as an ‘insurance policy’ to prevent a hard border?

When asked that question, Tanaiste Simon Coveney has been evasive, something which will have heightened the DUP belief that it is a point of vulnerability for Dublin and Brussels.

Last week also saw Michel Barnier state that “even in the absence of an agreement, we will do our utmost not to create a hard border in Ireland”, while the Polish foreign minister suggested that the backstop could be time-limited to five years, a proposal which is anathema to Dublin.

The shambolic state of the British negotiation has to some extent obscured these problems for Ireland.

On Tuesday, Sammy Wilson was quite open about the party’s desire, stating that “now is the time for the Prime Minister to exploit the chaos in Brussels and Dublin and press for a better deal”.

Significantly, that statement was endorsed by the party and released through its central press office rather than as a solo run by Mr Wilson.

However, the DUP faces two difficulties of its own. While it is influential, the party is not in charge of the British side of the negotiations and the prime minister has done little to suggest that she has the appetite or aptitude for the DUP’s methods.