UK 30 November 2018 The DUP do tolerate differences with Great Britain. But Brexit is different The party exists to secure and referee Northern Ireland's relationship with Great Britain and separation from the Republic. The backstop wouldn't let them. Getty Arlene on me. When your union's not strong Sign UpGet the New Statesman's Morning Call email. Sign-up There’s an increasingly hoary meme doing the rounds about the DUP. As Theresa May’s sometime parliamentary allies refuse to accept her Brexit deal on the grounds that it would create new regulatory differences between Great Britain and Northern Ireland, highlighting the party’s (ironically) catholic appetite for divergence with the mainland in the past has become easy sport. Critics of the DUP’s obstructionism on Europe have no shortage of grist for the mill. Most frequently cited is the party’s objection to the sort of abortion or same sex marriage legislation that applies in the rest of the United Kingdom. Then there is the fiscal divergence that it has spent recent years aggressively lobbying for: Westminster devolved corporation tax to Stormont in 2015, so that Northern Ireland’s rate could be aligned with that of – horror of horrors! – the Republic. There are other, as yet unfulfilled, demands for special treatment on Air Passenger Duty and VAT too. The party’s confidence and supply agreement included a government consultation on both, the subtext being that they too would probably end up devolved or differentiated at the DUP’s behest. It was happy to erect an Irish Sea border for libel law, too: in 2013 its Stormont ministers vetoed the extension to Northern Ireland of tougher defamation legislation that had just been introduced in England and Wales. Highlighting this litany of existing differences is neither difficult nor particularly unfair. Theresa May did so in the mildest possible terms when she visited Northern Ireland earlier this week, noting that there were already checks on food and agricultural products. Meanwhile the conclusion most often drawn by the DUP’s critics, with some satisfaction, is that they are either venal hypocrites or political poseurs prepared to leave their apparently devout unionist principles at the door if there’s a healthy serving of provincial pottage on the other side. There is a debate to be had about whether either judgement is accurate (and for most people it would be over rather quickly). It's also true that some of those matters are in theory devolved, and international relations are not. But really that is beside the point. What matters is that those perceptions exist, and that they appear to have some purchase at the very top of the Conservative Party. That they do explains why the government is in such a mess, and why, despite the Prime Minister’s frequent recourse to platitude about our precious union, she doesn’t really understand the politics of unionism at all. Central to all of this is the assumption that the DUP is above all else a party of the pulpit and the pork barrel. Chuck them another billion quid or threaten them with the legislation of equal marriage, the argument goes, and they’ll soon drop their objections to the backstop. It’s an easy line for exasperated folk in Westminster to take, and that’s precisely why it’s wrong. That isn’t to say that neither Christianity nor economic self-interest motivates their politics – they do. But too often those means are confused with the DUP’s ultimate political end. Fundamentally, it is a party of place, and more fundamentally how that place – Northern Ireland – relates to the rest of the United Kingdom and Ireland. As far as they and their voters are concerned, they exist to secure and referee the former relationship to their benefit and maintain a situation where Ireland is characterised by political separation. The success of their political project is defined not by the mere fact that the Republic is the other, but that they are the ultimate arbiters of Northern Ireland’s relationship to it. Whether that relationship is close in one sector or wildly different in another is by the by. Ultimately, what matters isn’t the divergence from Great Britain, but that unionism has some democratic recourse to affecting or changing it. The backstop – which would see Northern Ireland follow EU regulations over which the United Kingdom would have no say – would represent an existential failure of that political project in a way that a different rate of Air Passenger Duty doesn’t. The DUP could and would still act as a constitutional lender of last resort for unionist voters but, as Northern Ireland was sucked into Dublin's regulatory orbit, it would no longer have any claim to be a failsafe bulwark against creeping Irish unity. Even if Stormont were allowed a veto on new divergence, the parameters of that north-south relationship, and the regulations that defined it, would ultimately be set by Brussels and by extension Dublin. There are provisions in the withdrawal agreement for the joint EU committee that would notionally allow the UK government to resist the introduction of any new diktats from Brussels, but that still deprives the DUP of its most powerful political weapons and unique selling point – a veto and the means to wield it. It could no longer plausibly describe itself as that ultimate arbiter of the relationship between Dublin and Belfast and London, regardless of Northern Ireland’s headline constitutional status saying the same. This, not an aversion to another degree of admin for firms trying to ship from Stranraer to Larne, is what matters. There is no way facilitating the passage of a Brexit deal and the introduction of a backstop suit the DUP’s strategic self-interest, regardless of how good businesses tell them it would be for Northern Ireland. By their logic, championing fiscal divergence at Westminster enhances their claim to effective management of the union, accepting regulatory divergence brokered in Brussels doesn’t. It’s uncompromising and absolutist logic, but that is the very point of the DUP: they have prospered precisely because they are veto players. They sell themselves as the only party that can be trusted to guard and mediate Northern Ireland’s link with the rest of the United Kingdom. With no veto, they have no political game. Theresa May has still not reckoned with this fact. She should: it's the reason the DUP could pull the whole house down - and her premiership with it. › Why Donald Tusk’s warnings will do very little to help Theresa May Patrick Maguire was political correspondent at the New Statesman. Subscribe For daily analysis & more political coverage from Westminster and beyond subscribe for just £1 per month!