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<\/a>The Irish border has rarely been out of the British news in recent months. Yet, even now, it seems that many people in England have only sketchiest understanding of its nature and significance, apparent when <\/span>Channel 4 news<\/span><\/a> asked an admittedly unrepresentative sample of the public to draw it on a map of the island of Ireland. Yet this may be understandable. After all it is now essentially invisible, identifiable only by the change of road signs from miles to kilometres. An estimated 30,000 people cross it every day for work, using the 268 official crossings along its 499km length.\u00a0<\/span><\/p>\nBut it was not always like this. In 1923, customs posts were installed, dividing long-established communities, humorously described by Spike Milligan in <\/span>Puckoon<\/span><\/a>. There were strict checks in place between the 1930s and 1960s. People crossing the border were searched for contraband. Cars had to affix a sticker, or <\/span>Triptyque<\/span><\/a>, signifying that the vehicle had been temporarily imported from the other jurisdiction. The dense network of <\/span>cross-border trade<\/span><\/a> that existed before Irish independence collapsed.\u00a0<\/span><\/p>\n Customs checks were removed in 1993 with implementation of the European Single Market, but military checkpoints continued until 2005, in response to the violence in Northern Ireland, which caused the deaths of over 3,500 people (several who were my close friends or neighbours).\u00a0<\/span><\/p>\n In 1998, following ceasefires by the main paramilitary organisations, what is variously termed the Belfast or <\/span>Good Friday Agreement<\/span><\/a> was signed by representatives of most of the political parties in Northern Ireland, along with the British and Irish governments. This created new institutions within Northern Ireland, between the two parts of Ireland, and between the island of Ireland and Great Britain, paving the way for measures to promote peace and reconciliation. Although some violence has continued, most recently leading to the murder of a young journalist, <\/span>Lyra McKee<\/span><\/a>, the agreement has transformed relationships on the island of Ireland.\u00a0<\/span><\/p>\n This included co-operation in the area of health. The <\/span>Co-operation and Working Together<\/span><\/a> programme, largely funded by the European Union, promoted numerous cross-border care initiatives. However, the money came not from the EU\u2019s health programme (reflecting the Treaty provisions that health services are a matter for member states) but from its <\/span>peace and reconciliation<\/span><\/a> budget. Health services were seen as a way of bringing people together, with the added benefit of making it much easier for many people to obtain care in a sparsely populated rural area, where the nearest facility was across the border.<\/span><\/p>\n This was possible because Ireland and Northern Ireland were both in the EU. While people were always able to cross the border, thanks to the common travel area, the Treaty provisions on free movement of people allowed them to live in one jurisdiction and work in another, to accumulate pension entitlements, and to obtain healthcare. Free movement of services allowed an ambulance in one jurisdiction to transport a patient in another, while free movement of goods allowed it to carry morphine without falling foul of international law on trafficking narcotics and to administer a transfusion, without infringing rules on moving blood products, imposed by other countries in large part because of the UK\u2019s role in the BSE affair<\/a>. Treaty provisions on services also enabled the transfer of data, which underpins <\/span>many aspects of cross border care<\/span><\/a>.\u00a0\u00a0<\/span><\/p>\n Brexit threatens all of this. While some supporters of Brexit point to the very limited reference to the EU in the Good Friday Agreement, what it does say is fairly fundamental. The preamble states: \u201cWishing to develop still further the unique relationship between their peoples and the close co-operation between their countries as friendly neighbours and as partners in the European Union.\u201d Throughout the agreement there is an implicit assumption that this situation will continue, with references to cross-border workers, inland waterways, and cross-border health services. These would be <\/span>virtually meaningless<\/span><\/a> if there was a no deal Brexit. Quite simply, and as described above for health services, many of the mechanisms that make them work depend on the rules of the Single Market and Customs Union.<\/span><\/p>\n This was why, from the outset, both the EU27 and UK governments agreed that taking Northern Ireland out of the Single Market and Customs Union would be incompatible with the Good Friday Agreement. However, this created a major problem when Theresa May called an early election, leaving her majority dependent on the Northern Irish Democratic Unionist Party (DUP). Although Northern Ireland as a whole voted to remain in the EU, <\/span>by 56% to 44%<\/span><\/a>,\u00a0 the DUP, which was the only major party to refuse to sign the Good Friday Agreement, supported Brexit.\u00a0<\/span><\/p>\n Initially, Theresa May was agreeable to a situation in which <\/span>Northern Ireland would remain in the Single Market and Customs Union<\/span><\/a> even if outside the EU, as is the situation with the UK\u2019s <\/span>Sovereign Base Areas<\/span><\/a> in Cyprus (although they also use the Euro, which was not proposed for Northern Ireland). However, the DUP made clear that they would not accept this as it would require a border between Northern Ireland and Great Britain. Contrary to what is often alleged, it is simply impossible to have two territories, one inside either the Single Market and Customs Union, and the other outside it, and not have border infrastructure. This is for many reasons, and not as is sometimes suggested only for tariffs. Other checks include product regulation, VAT, and phytosanitary protection. Again, contrary to what is often alleged, there is no example of such a border without infrastructure anywhere in the world. Also, and for completeness, again contrary to what the DUP and others often allege, such an internal border would not be a precedent. There are many, including between EU and other states, for example in an <\/span>Italian<\/span><\/a> and a <\/span>German enclave<\/span><\/a> in Switzerland, the island of Heligoland. The \u201c<\/span>alternative arrangements<\/span><\/a>\u201d suggested by some as a means to avoid a hard border in Ireland are an archetypal example of what have been described as <\/span>Brexit unicorns<\/span><\/a>, or fantasies that don\u2019t exist anywhere.<\/span><\/p>\n Given her dependence on the DUP, Theresa May asked that the Withdrawal Agreement could avoid a border in the Irish Sea. Given the priority both parties gave to peace in Ireland, the EU27 agreed that, if no other solution could be found, Great Britain could remain in the Single Market and Customs Union. This went well beyond what the EU27 had initially been willing to agree as it did allow the UK to \u201c<\/span>cherry pick<\/span><\/a>\u201d.\u00a0<\/span><\/p>\n Those who understand the recent history of Ireland are virtually unanimous in believing that the inevitable border checks with a no-deal Brexit are incompatible with the Good Friday Agreement. Even if British politicians say they will not build border infrastructure, this is incompatible with their obligations under international law. Ireland has also said, repeatedly, that it does not want to do so, but the EU27 has made it very clear that it must to safeguard the integrity of the single market. As the <\/span>Financial Times<\/span><\/a> showed, a detailed look at even the seemingly mundane purchase of a bed in a situation where VAT regimes differ across an unguarded border reveals the necessity of such checks.\u00a0<\/span><\/p>\n In other parts of Europe border posts would be inconvenient, and markedly so for those transporting goods, as seen on the <\/span>French-Swiss border<\/span><\/a>, even though it divides countries with a <\/span>degree of alignment that is far closer than anything envisaged under a no deal scenario. They are not regarded as potential targets by those with the skills needed to make bombs, as they would be on the Irish border. The <\/span>Police Service of Northern Ireland<\/span><\/a> is clear that any infrastructure will immediately become a target. It will have to be guarded, and the guards will then become a target.\u00a0<\/span><\/p>\n Any prediction about Brexit now risks becoming out of date within minutes, but what is clear is that anything that creates a hard border on the island of Ireland, and that includes any Brexit that takes Northern Ireland out of the Single Market and Customs Union, is a threat to health. The British and Irish governments have both committed to ensuring the continued operation of cross border care. However, when a <\/span>Politico journalist<\/span><\/a> asked them exactly what legal mechanisms those providing services would use, the authorities in Dublin essentially said that it was up to those involved to find some while those in Belfast did the same but pointed to EU legislation that does not apply to international transfers. Once again, glib reassurances on Brexit flounder when confronted by the details.\u00a0<\/span><\/p>\n What we can say is that, first, and most immediately, it will reduce access to healthcare for those living along the Irish border. Second, it will affect those on the island of Ireland who depend on specialised care, including <\/span>paediatric cardiac surgery<\/span><\/a>, provided as an all-Ireland service. Third, any upsurge in violence will almost inevitably cost more lives, with a recent <\/span>bomb attack<\/span><\/a> near the border highlighting the reality of the threat. But that is only the start. A no deal Brexit presents an enormous and possibly existential threat to Northern Ireland\u2019s important agri-food sector. In a province with few other employment opportunities, it will be difficult to give a sense of hope to those affected, with potentially <\/span>tragic consequences<\/span><\/a>.<\/span><\/p>\n