As a regular visitor to Belfast, I'm bemused by the insistence of some people down here in the last few weeks, many of whom have not been in the North for years, that a united Ireland is just around the corner.    

When I make my monthly trip up there to visit relatives I get the Enterprise train to the old Belfast Central station and then stroll down to the Donegal Pass area where they live. It's about a mile or so and on the way, I usually stop off in St. George's Market for a coffee or even the famous Ulster fry. As well as all kinds of delicious treats, the vast red-brick Victorian market is full of stalls with antiques, books, furniture, and so on, a browser's paradise.

Although my accent gives me away, I'm always struck by how friendly everyone is. There is no feeling of being unwelcome, even if the stallholders like to crack the odd joke.  

This relaxed air, however, is an illusion. As I walk just a few blocks more to Donegal Pass near the city center, I enter a deeply divided area. Down the small streets on one side of the main road, the gable ends of the houses are painted in loyalist murals with UDA gunmen. On the other side, the walls are covered in IRA paintings and the street signs are in Irish.   

If you don't walk through these streets regularly, as I do, it's easy to forget how divided much of Belfast and the North still is. As I pass through the area these days there seems to be little day-to-day tension, even though the opposing communities are right beside each other.   

But it's hard to shake the feeling that it would not take much to set things off. And of course, there are many areas in the city where there are still high peace walls to keep the communities apart.   

The fact is that Northern Ireland is still a deeply divided society. The violence may be over and there may be peace and power-sharing, but that is still the reality.  

A lot of people here (and in Irish America) who have been having excited conversations in the last few weeks about the "inevitability" of a united Ireland would do well to take the Enterprise to Belfast and walk around a bit. It's a sobering experience.  

In the last few weeks, sparked by Brexit and the Northern Ireland Protocol row, this united Ireland debate has gathered some momentum here. Brexit has changed everything, the argument goes. We need to begin to discuss and prepare for the inevitable. It may not be imminent, but it's coming, and we need to get ready.  

Sinn Féin, not surprisingly, has been in the forefront of this push. A couple of weeks ago you will have seen the ad calling for a border poll which was placed in leading U.S. papers by the Friends of Sinn Féin.  

 "A United Ireland -- Let the People of Ireland Have Their Say" the simplistic ad was headlined, insisting that Brexit means we are now in a new era in which unity is on the table and a poll needs to be held without delay. 

Despite Brexit, however, it's much too early for that, as Taoiseach Micheál Martin has said repeatedly in recent months, not least because what is involved is complicated and difficult.  It was noticeable that the text of the Sinn Féin ad mentioned the unionists just once without going into any of these complications.    

The message in the ad was that we need to have the poll first and worry about the difficulties later. The Irish government, encouraged by Irish America, needs to start preparing on the basis that the outcome of the poll will be positive. And the implication was that the unionists will just have to accept it and move on from their past into a united Ireland. 

It's all a long way from the Taoiseach's vision of a shared Ireland by consent, from John Hume's recognition of the need to unite people rather than pieces of land, from Seamus Mallon's belief that we must bring unionists with us by persuasion rather than trying to force the end of partition by numbers.   

As we said here recently, the unionists have been in the North for 400 years, as long as the pilgrims and their descendants have been in America. They are Irish as well as British and that gives them rights as well as making any move to a united Ireland extremely complicated.

Yet the simplistic Sinn Féin attitude is that we will be as nice as pie to them, but the bottom line is they will have to suck up unity whether they like it or not. 

The debate on a united Ireland also emerged across the media here in the last two weeks, with leading commentators having their say. One of the main current affairs shows on RTÉ, Claire Byrne Live, devoted a lengthy program to it last week, with a variety of voices from across the political spectrum, including moderate and hardline unionists, taking part.   

The participants included the Fianna Fáil leader Martin and the Fine Gael leader Leo Varadkar, both of whom insisted that we can have a conversation but that it cannot be rushed and that many years of work needs to be done before the circumstances would be right for a poll on unity.   

The Taoiseach's shared Island policy, with the offer of €500 million to be spent by the Irish government over the next four years on cross-border projects that will benefit north and south, is a practical demonstration to unionists that we are prepared to put our money where our mouth is. It's about building trust and cooperation, not about setting a date for a border poll.  

The contribution of the North’s Justice Minister Naomi Long, the leader of the Alliance Party, echoed the point made above when she said that the North remained a deeply divided society.  

“How can you unite this island when in Northern Ireland we are divided and segregated?” she asked.

It's a fair point, one that Sinn Féin needs to take on board. No one imagines that healing the divisions in the North and building a unified society there in which genuine friendship between communities is the norm will be easy. But surely that must be the first step before the much bigger step of trying to make a united Ireland work?   

One of the most substantial contributions to the debate here last week came from a Fianna Fáil member of the Dáil, Jim O'Callaghan, a lawyer who is seen as a contender to replace Martin as leader of the party whenever there is a change. In a major speech given at Cambridge University in the U.K., he listed a number of things that would be needed for a united Ireland.  

These included a new Constitution, a guaranteed number of unionist ministers in government, a new structure with the Irish Parliament to sit in both Dublin and Belfast, and other fundamental changes that go much further than simply having a new flag, national anthem, possibly joining the Commonwealth, and so on.   

None of this would be easy for traditional supporters of Fianna Fáil, the party of de Valera which regards itself as the real republican party. O'Callaghan put some distance between himself and Martin by saying that it was right that we should begin to prepare for the possibility of a border poll. But he tempered this by adding that it was likely “at some stage over the coming decade,” a timescale that is very different from that of Sinn Féin.  

RTÉ commissioned a national opinion poll to go with Byrne’s show last week which showed that 53 percent of people in the Republic were in favor of a united Ireland, 19 percent opposed, with 28 percent saying they don't know. The surprising thing about this was how low the number in favor was – 53 percent is hardly a ringing endorsement of unity, particularly when compared with polls over the last ten years which often showed 80 percent or 90 percent in favor.

This may be an indication that the more people in the south think about what is involved, the less enthusiastic they are. First, there is the potential for violence and disruption.  

There is also the enormous cost that unity will mean for taxpayers here. Even if it is considerably less than the £12 billion Westminster currently gives to fund the North every year, it would still be very substantial. And support from the U.K., the EU, and the U.S. to lessen that bill might not last very long.   

The problem for Irish taxpayers is that we face an enormous financial challenge in the years ahead because of the Covid debt and the Brexit hit to our economy. The tax burden to deal with that is likely to be daunting enough. 

Many may feel this is not the time to take on even more. Despite all the talk about a united Ireland, there is no guarantee that a majority in the Republic would vote for it even if the unionists were in reluctant agreement.