Nearly 16 months after an ailing Martin McGuinness resigned as Northern Ireland’s deputy first minister, bringing its devolved government down in the process, no solution to the province’s constitutional impasse is forthcoming.

Sinn Fein and the Democratic Unionist Party have failed to broker the powersharing agreement necessary to restore government at Stormont and show little inclination to do so.

Both James Brokenshire and his successor as Northern Ireland Secretary, Karen Bradley, meanwhile, have proven pathologically unwilling to reintroduce direct rule from Westminster – despite recent calls from their government’s unionist partners to do so.

Instead, Northern Irish politics has operated in a curious and confusing limbo. Both secretaries of state set budgets from Westminster, but chose to indulge the fiction that the restoration of power-sharing was a live prospect (which, save for a few fleeting moments, has seldom been the case) rather than legislate to introduce direct rule from Westminster.

That, in practice, has meant civil servants taking day-to-day decisions for Northern Ireland – not just administrative ones, but increasingly political ones too. Such decisions, like the approval of a planning application for a £240m incinerator in Mallusk, Co Antrim, by a civil servant last September, are unglamorous but essential to the business of running a country.

Civil servants have complained such decisions are beyond their competency. And in the continued absence of elected politicians, they are also constitutionally ambiguous. Where is the democratic accountability? What right do unelected officials have to pursue a policy agenda above and beyond existing policy? With no prospect of a devolved government returning anytime soon, what right do they not to?

For the past 15 months, these questions have, for the most part, stayed rhetorical. Yesterday, however, the High Court gave an answer. A judicial review found that civil servants did not have the power to have approved the Mallusk incinerator, and concluded that it could not be assumed that "such decision-making would continue in Northern Ireland in the absence of ministers without the protection of democratic accountability".

The upshot of this is that governing Northern Ireland by direct rule lite – with a Westminster-set budget and civil service-led administration – is now close to completely untenable. Other seemingly routine decisions face similar questions.

The effect of yesterday's ruling is twofold: not only could it constrain civil servants in a real, legal sense, but its chilling effect will discourage them from taking any decision, however necessary, that could leave them open to a further judicial review.

Drifting with no ministerial oversight will no longer cut it. The government has had its bluff called and must clearly now do something. Legally, that something can only be a new assembly election, or direct rule. On balance of probabilities, the former, bitterly confrontational and inconclusive as it would likely be, would bury devolution rather than save it.

Direct rule, which would further corrode the limited stock of the government among nationalists and in Dublin, would prove just as toxic. Calls for the introduction of the British-Irish intergovernmental conference have gone unheeded. But if the months since the vote for Brexit have proved anything, it's that the government has the stomach for taking decisions that irritate the green side of the argument.

So why not direct rule? The real anxiety preventing action by ministers and officials is that governing Northern Ireland effectively from Westminster will prove near-impossible on a legislative timetable already choked by the demands of Brexit. Yesterday's decision, however, means that they are going to have to try.

The government's defining mission will now be complicated not just by the dreary steeples of Fermanagh and Tyrone, but by the electricity interconnectors of Armagh and incinerators of Antrim too.