One hundred years ago this week, a peace agreement was signed in London between British and Irish politicians that aimed to put an end to centuries of intermittent, but intense, conflict between the two countries. The Anglo-Irish Treaty of 1921 allowed for the establishment of an independent Ireland, while also allowing Northern Ireland to remain within the UK. It was always a stop-gap arrangement, designed to defuse an escalating war while satisfying the aspirations of the two historical traditions of Ireland — Catholic nationalist and Protestant unionist. Perhaps the agreement was the best that could have been devised in the circumstances but, on the evidence of the past century, it was deeply flawed. All that followed — the Irish Civil War, trade disputes with Britain, the impoverishment of immigration, and sporadic and low-level sectarian violence culminating in nearly three decades of open warfare during the Troubles — show the treaty to have been an abject failure. So how ironic that now, in the wake of Brexit and amid rising populist nationalism in the UK under Boris Johnson, the end of the treaty era looks in sight. The reunification of Ireland under one political system appears more likely and more imminent than at any time since the Act of Union in 1801 that set up the UK. Full disclosure: I am an Irish citizen and believe that the reunification of Ireland is a legitimate aspiration and a desirable goal — as long as it is achieved with the consent of a majority within the whole of Ireland and, crucially, with the consent of the people of Northern Ireland. For most of the past 100 years, it looked extremely unlikely that such a majority would come in the north. The state, sometimes misleadingly called Ulster, was set up explicitly to keep Northern Ireland in the UK and London underwrote that goal, constitutionally and financially. The founders of Northern Ireland were acutely aware of the demographics. Because Catholic nationalists had a higher birth rate than Protestant unionists, at some stage they would overtake them in population terms and likely vote for a united Ireland. So a whole arsenal of techniques was employed to ensure that nationalists born in Northern Ireland would not want to stay there much past voting age. Discrimination in housing and employment, alongside the actions of a blatantly sectarian system of law and order, meant many Catholics gave up on their own country and left — for Britain, the US and other parts of the world. Not many went to the Republic of Ireland, which speaks volumes about the other failure of the treaty. The independent Irish state it created was poor, conservative and dominated by the Catholic Church to such an extent that even their co-religionists in the north did not want to live there. All that began to change with the entry of Ireland into the EU in 1973, at the same time as the UK. Capital began to flow from Brussels to the whole of Ireland, but more to the poorer south. Things began to look up in the republic, just as the north was descending into sectarian mayhem. Socially and culturally, too, Ireland was changing. It was becoming more liberal and tolerant, less Catholic, even though the vast majority still formally ticked the box labeled “RC” for Roman Catholic (as do I). By the early 2000s, the Celtic Tiger economy was roaring in the south. In the north, the economy was improving, too, largely thanks to the 1998 Good Friday Agreement, which effectively ended the Troubles. The vote for Brexit in 2016 threw all this up in the air. The north voted to remain by a big majority, underlining the difference between it and the rest of the UK. The frontier between the two parts of Ireland — often a killing zone during the Troubles — was suddenly the only land border between the UK and the EU, and nobody wanted to see it closed down again in a renewed cycle of violence. To avoid this, the Johnson government put the border in the Irish Sea, effectively making Ireland a common economic and customs zone, including the north. Die-hard unionists did not like that, but the effect has been transformational. Trade between north and south is at record levels, while exports from Ireland to the UK are also booming. Meanwhile, Catholic nationalists — no longer forced into exile by economic and sectarian pressure — are approaching a majority in the north. Nobody can say when it will happen, but at some stage in the next decade, they will be dominant. There is one big unknown: How will unionists react when they find themselves in a minority in their statelet? Given the history, the auguries are not good. The choice is between peace, economic development and rising living standards under a united Ireland and sectarian violence and conflict under the terms of the Anglo-Irish Treaty. As its era draws to a close, Ireland is at a historic crossroads. Frank Kane is an award-winning business journalist based in Dubai. Twitter: @frankkanedubai Disclaimer: Views expressed by writers in this section are their own and do not necessarily reflect Arab News" point-of-view