Arlene Foster holds the key to Brexit and the future of Europe

It is critical the DUP leader brings unionism with her in accepting the prospect of distinctive treatment for Northern Ireland

You may not realise it, but Arlene Foster is one of the most powerful politicians in contemporary Europe. In the bizarre and tumultuous state of British politics, this fact is one that will stand among the most historically significant. It is an extraordinary situation. Foster is a member of a regional legislative assembly that hasn’t sat for nearly 1,000 days, the leader of a party with just 10 MPs, and the subject of an inquiry that may well see the end of her political career within weeks.

But at this time, she holds the key to Brexit. And the stability of the pound, the constitution of the UK, the size of the European Union and the future of the continent are in no small way affected by her decisions.

It is critical Foster brings unionism with her in accepting the prospect of distinctive treatment for Northern Ireland

So what is Foster proposing? Her apparent acceptance of a Northern Ireland-only solution stands out in luminescent colours from her recent comments in Dublin. But we should not assume that this clears the way for a Northern Ireland-specific backstop returning to the table, and thus speeding us through to the withdrawal agreement.

Having spent the past two years being decisive about very little, other than resistance and naysaying, Foster is now under a great deal of pressure to move away from her “blood-red line” against any post-Brexit differential between Northern Ireland and the rest of the UK. Even those pushing alternative arrangements acknowledge that there is no way around putting some controls in the Irish Sea after Brexit. It was in Dublin, of all places, last week, where Foster decided to push forward. The question being asked across the European continent now is: how far did she move?

In some ways, it could be seen to be a moot point. If Boris Johnson can lose almost two dozen of his party’s MPs without so much as a shrug, why would he worry too much about what the DUP thinks? The loss of the confidence of the DUP, which long failed to supply his predecessor with the promised votes, is hardly a game-changer.

But the truth is that what the DUP does now will have a determining role in Northern Ireland’s future – for better or worse. And, with that, it will shape the whole outcome of Brexit, including whether it leads, sooner or later, to the dissolution of the United Kingdom itself.

It is absolutely critical that Foster brings unionism with her in accepting the prospect of distinctive treatment for Northern Ireland. This is no small task. Unionism has rallied behind the notion that the withdrawal agreement is anathema to the union itself. Polls have shown that, in the space of a year, support for the backstop among unionists in Northern Ireland has plummeted. This is in no small part owing to the antagonism towards it led by Foster herself.

There is a risk that the UK could exit the EU with a deal but at the cost of stability in Northern Ireland. If unionists are left feeling betrayed by the DUP, then perhaps the party could seek to regain credibility by offloading Foster as leader. But if unionists are left feeling shafted by the British government, then it means a breakdown of trust that will be incredibly difficult to restore.

Of course, the nature of Northern Ireland means that this tension works both ways. If the pressure for a deal sees the Irish government concede so much on the withdrawal agreement that nationalists in Northern Ireland feel exposed and vulnerable, then this too would rock the foundations of the peace process.

Looking more closely at what Foster said in Dublin, it remains fairly clear that the tension that has always been there in DUP (and Conservative party) aspirations for Brexit remains absolutely entrenched: that is, the stubborn belief that it is possible for the UK to leave the single market and customs union yet there be no trade barriers within the UK, and frictionless trade on the island of Ireland.

The backstop cut through this tension but left unionists and Brexiters feeling hard done by. But the backstop is a notion and term that is more toxic for unionists than that of “all-island arrangements”.

Indeed, Foster notes that the DUP “recognises the unique history and geography” of Northern Ireland, which in turn gives a certain logic to specific arrangements for Northern Ireland. While this is something the party has flatly contradicted in repeated comments over the past year, it can also claim that this has long been its position.

In its 2017 manifesto, the DUP sought Northern Ireland-specific solutions, and it wanted to see the “particular circumstances of Northern Ireland” fully reflected in the negotiations.

It is significant that there are strong similarities between these aims and those of all the other main parties in Northern Ireland. Sinn Féin has long argued for special designated status for the region. The Alliance party has argued for a special deal for Northern Ireland. The SDLP has argued for its “bespoke” status. And the Ulster Unionists have sought its designation as a special enterprise zone.

If Foster can now act to solidify this common ground between nationalists, unionists and others in Northern Ireland, and if she can steer a path towards an acceptable withdrawal agreement and future deal, it would be a rare and momentous act of leadership that could change the course of European history.

Katy Hayward is reader in sociology at Queen’s University Belfast and author of Bordering on Brexit

Guardian Service