Northern Ireland has now been without a power-sharing executive for just over four hundred consecutive days. That’s considerably longer than the four months Angela Merkel spent trying to form a new coalition in Germany, but rather less than the record five hundred and eighty-nine days that Belgium went without an elected government, back in 2010-2011.

This week, expectations were raised that the two largest parties, the DUP and Sinn Fein, would finally agree to restore devolution. Theresa May, who was careful previously not to become embroiled in Northern Ireland’s latest political impasse, flew into Belfast to participate in negotiations.

Ulster’s politicians are stubbornly reluctant to be hurried, even by effective world leaders, and the prime minister did not get to announce a breakthrough. On Monday, the DUP began to cool speculation that an executive would be formed quickly. Then yesterday, its party leader, Arlene Foster, announced that the current round of discussions had concluded unsuccessfully and there was no imminent prospect of an agreement.

A senior assembly member, Simon Hamilton, suggested that May’s visit had formed “a bit of a distraction”, that wasn’t “entirely helpful in getting us to reach a successful conclusion”; though some of the party’s opponents claim that a deal had been agreed and that Mrs Foster was unwilling or unable to sell it to ‘grassroots’ unionists.

Her statement highlighted ‘serious and significant gaps’ between the DUP and Sinn Fein over an Irish Language Act, which formed part of a lengthy list of ‘red-lines’ that republicans said must be satisfied before they would return to government. Unionists were suspicious that this legislation would be used to boost the number of Irish speakers in the public sector through ‘affirmative action’ and impose costly, divisive dual-language signage.

Sinn Fein certainly didn’t hide its aspirations to use the act to promote “Irish national identity”, on the basis that Northern Ireland “is not British”, as its northern leader, Michelle O’Neill asserted before Christmas.

The DUP was prepared to discuss minority language protection as part of a wider culture package, but it couldn’t possibly persuade the unionist electorate, which is practically unanimous in its opposition to the type of act sought by Sinn Fein, to support ‘free-standing’ legislation.

Even if Foster had been prepared to push through a language bill, it’s difficult to envisage how any agreement would have stabilised the Stormont executive in the longer term and made it less prone to collapse. The current system rewards parties that undermine power-sharing and pursue their grievances outside the Assembly, whenever they don’t get their way.

Northern Ireland’s democratic institutions have been suspended regularly ever since they were formed in 1998, under the provisions of the Good Friday Agreement. Though it’s often their misbehaviour that causes power-sharing to collapse, Irish republicans in Sinn Fein have been most adept at exploiting these mini-crises and making their participation in the executive contingent on lengthy lists of demands.

Short bursts of regional government have been accompanied by much mutual backslapping, so it’s easy for people in Northern Ireland, let alone the rest of the UK, to forget just how dysfunctional Stormont has become, particularly over recent years. Political talks and negotiations are at least as commonplace as a working Assembly. And none of the talks or agreements that allowed devolution to lurch on unsteadily actually resolved any of the underlying issues causing instability in the first place.

Back in December 2014, the parties signed the Stormont House Agreement, which, among less tangible provisions, committed them to implementing David Cameron’s government’s welfare reform programme, in return for a hefty financial package.

Less than a year later, the DUP and Sinn Fein were back in ‘hothouse talks’. On that occasion, unionist first minister, Peter Robinson, withdrew his ministers from the executive, after the police blamed the IRA for killing Kevin McGuigan, a former member who had fallen out with the organisation. The DUP argued that it could no longer govern with a party whose paramilitary wing was still active and violent.

Yet, with astonishing chutzpah, given that their movement was quite literally accused of murder, republicans made further demands around welfare and Troubles inquests when negotiations started, before even more money from Westminster lubricated the ‘Fresh Start’ agreement.

The latest dispute was ostensibly caused by the involvement of Arlene Foster in a failed green energy scheme, that overspent by approximately £700 million when she was minister at the department of enterprise, trade and investment. In January 2017, the late deputy first minister, Martin McGuinness, resigned after she refused to step aside as first minister while the Renewable Heat Incentive was investigated.

Tellingly, that issue was practically invisible during subsequent talks, as Sinn Fein focussed instead on its shopping list of ‘red lines’.

Some of its demands – like the legalisation of same sex marriage – were adopted opportunistically, to portray unionists as old-fashioned and ‘regressive’. Others – like the Irish Language Act – and legacy inquests into deaths attributed to the security forces – are bound up with a broader campaign to undermine Northern Ireland’s place in the UK and alienate Irish nationalists from the British state.

Whether the relevant issues are sensitive matters around identity, paramilitarism and the past, or quite ordinary, everyday debates, like welfare provision, business taxes and selective education, almost any dispute can become a touchstone of the ‘peace process’ and form an excuse for Sinn Fein to pull down power-sharing.

If Stormont is restored eventually, it will only be a matter of time before it collapses again, unless a potential deal removes the incentive to create crises and dismantles the larger parties’ power to veto any legislation that they deem sensitive. That means reforming the institutions established in 1998, which, in the glow of optimism after the agreement, were always intended to evolve as the province’s political system matured.

In the interim, the government must finally show some backbone and exercise the powers that are supposed to be devolved to the Stormont Assembly.

So far, the Conservatives have doggedly refused to introduce direct rule in Northern Ireland, which has delayed important policy decisions and put power in the hands of unaccountable civil servants.

Already, the statutory deadline to agree the province’s 2018-19 budget is looming. There’s no more time to be cowed by the Irish government, which, completely contrary to every previous agreement, is angling for a role in Northern Ireland’s governance in the absence of devolution.

A short, sharp spell of government from Westminster is now unavoidable. It’s the only way that long-deferred decisions can be taken to reform the province’s antiquated health service and education system. It may even provide the shock that finally persuades politicians in Northern Ireland to take responsibility and return to their executive posts.