Brexit supporters’ main reason for leaving the European Union is for the U.K. to regain control over its own borders — in the EU there is free movement between all Union countries.
That creates a unique situation with Ireland. The open border between the independent Republic of Ireland and the U.K.’s Northern Ireland is a major part of the peace treaty that ended decades of violence commonly referred to as The Troubles.
Brexit supporters don’t want free movement between the U.K. and the EU, and the Republic of Ireland is part of the EU.
Brief history of the border
The U.K. separated the island of Ireland into two states in 1921: a mostly Catholic Southern Ireland and a mostly Protestant Northern Ireland. The independent Irish state was a dominion of the U.K. from 1922 until 1949 when it became the Republic of Ireland.
During the Troubles, the border hardened between the nations as checkpoints and watchtowers were set up and the border was virtually impassable.
As a stipulation of the 1998 Good Friday Agreement, the border crossings were removed and free movement was reinstated between the two countries.
There are over 250 roads that cross the border as of 2018, and millions of people cross it monthly.
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What does the draft Brexit deal decide?
The deal commits the two sides to a “backstop” solution to guarantee the border between Ireland and the U.K.’s Northern Ireland remains free of customs posts or other obstacles.
The backstop would put the U.K. in a customs arrangement with the EU, and will last until superseded by permanent new trade arrangements.
Both sides say they hope to have a new deal in place by the end of 2020, so the backstop is never needed.
What could the new deal be?
“You can’t not have a border if you’re going to get out of the European Union,” Mel Cappe, University of Toronto professor and former Canadian High Commissioner to the U.K., told Global News.
He explained there’s two places where the border can be drawn: either through the Irish sea between the island of Ireland and the Island of Great Britain, or between the six counties of Northern Ireland and the republic.
“If you draw in the Irish Sea, you are no longer the United Kingdom of Great Britain and Northern Ireland,” Cappe explained.
And if officials institute a hard border with checkpoints at the six counties of Northern Ireland, that violates the Good Friday Agreement.
Theresa May has said both options are not acceptable.
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Another option is to keep the backstop option of a customs union, as it means “people and goods can move freely across the border, and you have a common external tariff for all other countries,” Cappe explained.
But that means the EU would be able to set the tariffs, and the United Kingdom would have to live by them —without having a seat at a table to decide the tariff.
“When you’re in a customs union you have to take your marching orders from Brussels,” Cappe explained.
That’s why pro-Brexit politicians like Boris Johnson say the deal is unacceptable — and why major Brexit ministers and aides have resigned.
“I cannot reconcile the terms of the proposed deal with the promises we made to the country in our manifesto at the last election,” Brexit minister Dominic Raab said in his resignation letter.
Northern Irish unionist party currently propping up U.K. government
The Democratic Unionist Party — the Northern Ireland political party that supports being in the U.K. — is the party that is currently propping up Theresa May’s Conservative minority government.
The DUP has threatened to pull its support from the minority government if the backstop agreement means the province is treated differently from mainland Britain.
Asked in an interview with BBC Radio Ulster whether his party would vote against the deal, DUP MP Jim Shannon said “we certainly will. … We feel very much betrayed.”
Without the support of the DUP, May might not have the votes to approve the Brexit deal, once it comes up for a vote.
Could Northern Ireland leave the U.K.?
As part of the Good Friday agreement, Northern Ireland has an option to join Ireland if it desires.
The Northern Irish party in favour of leaving the U.K., Sinn Fein, could use this as an opportunity to promote reuniting the two countries.
During the Brexit referendum in 2016, 55.8 per cent of Northern Ireland voted to remain in the EU. Turnout was 67.2 per cent, meaning there were 440,707 votes to remain, according to the BBC.
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What do people in Northern Ireland have to say
“We need no border. We can’t go back to that. We signed up to a peace accord, to retain free movement in Ireland and we need it and we have to stick to it. A hard border would just destroy the whole community.”
— Gerrard Crowe, 53, of Ballyconnel, Ireland.
“I am worried. I think Theresa May, you know, has actually tried to do the best she can. But she’s up against a lot of opposition. I think the DUP needs to really think about the people of Northern Ireland.”
— Sylvia Brough, 39, of Northern Ireland.
“I suppose fair play to Theresa May. She battled on rightly, like. She’s seen to have got the deal, here, that, well, …it’s going to be the best of a bad lot, like. At least with staying in the customs union, will probably be the best and from a lot of the talk it’s the best for Northern Ireland.”
— Sean McGovern, 60, of Northern Ireland.
“There probably has to be another general election and then another vote on Brexit. Bottom-line that is it. Nothing else is going to suffice.”
— Patrick Maguire, 44, of Northern Ireland
— with files from the Associated Press and Reuters