Readers respond to an article by Fintan O’Toole in which he said that the PM’s false claims about the withdrawal agreement reveal an utter lack of interest in the consequences of Brexit for Belfast and Dublin

Fintan O’Toole is of course correct that “Johnson has no real knowledge of or interest in the consequences of the withdrawal agreement – and of Brexit itself – for Northern Ireland” (One thing this victory doesn’t change: his lies about Ireland, Journal, 16 December).

The potential Northern Ireland protocol is a disaster waiting to happen. There’s an unclear requirement, a management-imposed deadline, an uncertain regulatory environment with two supervisory bodies renegotiating their relationship, a diverse user base including government and businesses, and no defined business model.

Commercial organisations will need to interact with new and probably changing government requirements, and will need to assess whether trading across the Irish Sea is still worthwhile in the light of the new requirements.

I have successfully managed cross-industry developments interfacing with thousands of customers, and managed their redevelopment over three years, in a commercial environment. This Northern Ireland protocol doesn’t stand a snowball’s chance in hell of being implemented successfully in 2020 or 2021.

Of course, if it is just a case of “any deal will do” to fool the electorate, as a segue to a 2020 no-deal, then the practicality wouldn’t matter to the government. But in that case we are being played for fools by Boris Johnson. Again.

Mike Cashman

Author, Brexit’s a Trick not a Treat and Brexit’s a Musical Trick

• Fintan O’Toole is right to be concerned about the sense of abandonment faced by the unionist community in Northern Ireland. They have been badly served by the DUP and face a very uncertain future if Johnson’s deal is implemented unamended. His deal runs the risk of crippling the Northern Irish economy and is unlikely to be tenable in the short to medium term.

The trouble with offering a united Ireland as an alternative to Johnson’s deal is that it offends the bipartisan spirit of the Good Friday agreement and would encounter much resistance from unionists in the north. However, a different alternative is possible.

If Johnson does not pivot towards a soft Brexit, he antagonises his fellow citizens in both Northern Ireland and Scotland. If directed positively this antagonism could fashion a different set of political arrangements on these islands.

A newly independent Scotland remaining in the EU could enter into a new Good Friday-type arrangement with the Republic of Ireland, giving security to the unionist community. The EU could help foster these arrangements as part of its discussions about the new relationship with England and Wales.

Dr Paul Lally

Liverpool

• Fintan O’Toole rightly says: “Johnson has no real knowledge of or interest in the consequences of the withdrawal agreement – and of Brexit itself – for Northern Ireland.”

Maybe Boris Johnson will wake up when there are repercussions on the mainland. An unsettled Northern Ireland will almost certainly mean an unsettled Glasgow, Liverpool, Manchester and other places with large populations of Irish descent. The peace process led to peace on those cities’ streets. But the current uncertainties have already led to some sectarian disturbances in Glasgow, which took the police by surprise.

An ignorant Johnson will thoroughly deserve further sectarian marches and probably disturbances at football matches and around churches. But those of us whom he tried to mislead about the whole Irish implications of Brexit won’t deserve it. Nor will the people of Northern Ireland whom he tried to hoodwink or their kin in mainland Britain.

Professor Emeritus Lalage Bown

Shrewsbury, Shropshire

• The prime minister’s mendacity about Ireland, as discussed by Fintan O’Toole, is compounded by the fact that over two-thirds (68%) of people in Northern Ireland voted for parties that wished to remain in the EU – an increase of 12% from the 2016 referendum.

Paddy Hillyard

Belfast

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