But that almost certainly won't lead to any short-term change in constitutional arrangements. Since the bust of the Celtic Tiger economy in the Republic of Ireland and the associated Irish banking crisis, there has been little appetite among northern Catholics for political union with the south. British health, education and salary provisions are better than the republic's. But the biggest winner from the Good Friday Agreement in the north has been the Catholic middle class. Northern Ireland was a state designed to perpetuate Protestant privilege. Now the state is committed to being a meritocracy.
And what do we find in that meritocracy? The cohort that does best at school is middle-class Catholic girls (middle class defined as not qualifying for a free school lunch). They do so well they are challenging the best performing cohort in all UK schools, ethnic Chinese kids. And the cohort that performs worst in Northern Irish schools is working-class Protestant boys, many of whom go on to marching bands and violence.
A lot of Ulster's middle-class Protestant kids go to university in northern English and Scottish cities and don't come home. They feel out of place in Northern Ireland. They can never identify with the Gaelic Irishness of the republic and the northern nationalists, but neither do they identify with the old-style unionism of their grandfathers.
As they lose their electoral majority, the Unionists are steadily losing their symbols, and it's driving them nuts. Already, there are more Catholics than Protestants in Belfast. So the city council is not inclined to fly the Union Jack. Polls show that only about 40 per cent of Northern Irish regard their primary civic identity as British. Twenty per cent say they are Northern Irish and another 20 per cent say they are just Irish. So while the nationalists cannot take Northern Ireland out of the UK, they are taking the UK out of Northern Ireland.
Although broadly peaceful, and certainly preferable to "the Troubles", this is still a situation full of danger for everyone. Gaelic cultural nationalism is flourishing in the north. Ireland's history suggests that cultural nationalism is the surest route to political nationalism. If the Scots should vote to leave the UK in December, unlikely but by no means impossible, or even if Edinburgh keeps pressing for ever greater devolved powers, the dynamic for Gaelic separatism in the north must be affected.
And Northern Ireland is still a bitterly and profoundly divided society. There are still physical barriers between Catholic and Protestant communities in Belfast. Very few children attend mixed schools. Hundreds of people still receive assistance because they are forced to sell their homes - they are the wrong religion in someone else's patch.
And while Northern Irish politics has domesticated the extremists, it has also empowered them. Sinn Fein and the Democratic Unionist Party have replaced the more moderate political parties that once dominated their respective communities. Most Catholics, though full of grievance for their unequal treatment in the past, never supported violence. But many of them vote Sinn Fein now because they think Gerry Adams and Martin McGuinness are tough, effective negotiators. If politics is to be a communal arm wrestle, let's put some muscle into it, as one wag observes.
Politics, like life, is full of anomalies, of formulas that should work but don't, and of situations that should never work but do. Northern Ireland could continue as it is, with all its demographic and political trends unfolding, uncomfortably but peacefully, for many years.
On the other hand, it could easily get very ugly again.
