When the draft legal text was published on Wednesday, Irish and EU officials assumed the duck-and-cover position: they fully expected a furious backlash from London and the DUP.
One senior Irish source warned the reaction could be "cataclysmic".
This is the realm we are now in.
A political agreement was reached between the EU and UK in December, and it was now being converted into a legal text. The ambiguities and sensitivities of the deal were always going to look much starker when enshrined in a legal document.
EU officials and member states are fully aware of how toxic the Irish border has become. But the European Union is built on complex legal foundations, and the kind of constructive ambiguity that might allow unionists and nationalists to equally claim victory in Northern Ireland will not work with Brexit.
Member states regard the Irish border as a mechanical issue.
"Because it’s such an emotional and volatile question," says one EU official, "you have to approach it from a very technical and pragmatic approach.
"You can’t afford sentiment to carry you over into a situation where you make mistakes that are more painful in the longer run and poison the issue further."
So, better to confront the issue head on, and wait for the debris to settle.
"Everyone’s resigned to the fact that we don’t have a better way of doing this. The Irish issue was going to explode anyway. Better now than in October.
"One way to diffuse the situation is to put these hard facts on the table now rather than confront them later. You are talking about things that are dangerous.
"At the same time, rationally, all of this is the translation into a legal text of the principles that were agreed in December. There’s just no other way around it, and no better solution."
By all accounts, the process of drafting Wednesday’s legal text was an intense experience.
Officials from the EU Task Force, aided by experts from the European Commission and the European Council legal services, worked flat out from mid January.
The text was finally "stable" on Thursday 22 February and ready to be presented to the weekly meeting of the 27 EU Commissioners the following Wednesday.
So sensitive was the document that the 27 heads of cabinet within the Commission were only entitled to examine the document in a "reading room" before it was published.
December’s political agreement envisaged three ways to avoid a hard border.
Option A - London’s preference - is that a future trade agreement will be so deep that trade will be frictionless, and a hard border will not be needed.
Option B is the use of technology and exemptions if Option A does not work.
Option C is the "default", keeping Northern Ireland aligned with the rules of the customs union and the single market in order to avoid a hard border.
"In the absence of [Options A and B]…," the December agreement reads, "the United Kingdom will maintain full alignment with those rules of the Internal Market and the Customs Union which, now or in the future, support North-South cooperation, the all-island economy and the protection of the 1998 Agreement."
British officials were not part of the drafting process for Wednesday’s text. There were, however, regular contacts.
London was told the general direction of travel, but could not directly influence the evolution of the text.
Sources say, however, that they did as much as possible to limit the presence of the backstop, even to the point of wanting Options A and B in the body of the text, while the backstop would go into a Protocol.
That did not happen.
However, drafting officials were sensitive to UK demands. They tried to keep the text as neutral and technocratic as possible.
But some phrases could not avoid jumping out.
The territory of Northern Ireland could be "considered" part of the EU customs territory. There would be a "common regulatory area".
A closer reading of the draft text shows that the Task Force has kept explicit alignment to a narrow range. "We’re not saying that Northern Ireland has to apply the whole acquis communautaire [ie, the entire body of EU law]," says one source.
"It is about the movement of goods and where that gives rise to problems."
So the text focuses mostly on things that would normally need to be checked at an EU-third country border: goods, which have to be controlled for customs and compliance with EU regulations and standards; the production of agrifood, fisheries and the movement of live animals, which require a whole range of certification and paperwork; things like invasive plant species; the wholesale electricity market.
A senior EU official emphasised the limited nature of explicit alignment.
"The list of the issues not covered is a lot of longer. It does not cover free movement of services, capital, persons [which is covered by the Common Travel Area], establishment, employment policy, social policy, the European Social Fund, educational and vocational training, public health, consumer protection, sport, culture, industry, social and territorial cohesion, RTD and Space, Trans European Networks, social policy, tourism, civil protection."
The draft text holds out the potential for further alignment if it is required to facilitate North-South cooperation. There is a series of annexes in which these areas will settle later.
These could include rules on "the environment, health, agriculture, transport, education and tourism, as well as energy, telecommunications, broadcasting, inland fisheries, justice and security, higher education and sport".
A Joint Committee, including, it is understood, officials from Northern Ireland, would monitor how the Protocol is being applied so as to successfully maintain North-South cooperation.
The draft is just that, a basic text that will be the subject of negotiation with the UK. That negotiation will only get under way when officials from the 27 member states have gone through the document in detail. It is not expected, however, that the other member states will recommend any changes to the Irish protocol.
The UK is particularly sore that Paragraph 50 is not featured in the draft text.
This was the reassurance to unionists that Northern Ireland remaining in the customs union would not simply shift the border to the Irish Sea.
EU officials and member states were adamant, however, that that was a promise made by the UK to the DUP, and not an EU guarantee.
The only comfort for the UK was Article 15 of the draft Treaty, which suggests that if other solutions were found that avoided a hard border (and maintained the integrity of the internal market), then backstop need not apply.
But officials say there is widespread dismay at any attempt portray the Irish protocol as the EU "weaponising" Northern Ireland in order to push for a particularly soft Brexit.
There is also frustration that Theresa May had not, to date, spelled out in detail what kind of customs relationship the UK wanted.
"If she’d actually moved her lines on that earlier," says one official, "none of this would have been necessary. It’s the entrenching of these redlines that means, well, we need to really spell out what this means for Ireland."
In the light of Theresa May’s Mansion House speech, EU officials and member states will want to hear more about where exactly the UK wants to align with the EU regulatory order, and what she means by a customs partnership.
The UK still regards their paper on Ireland last August, which recommended technological solutions to customs checks, as credible, even though it was dismissed by Brussels as "magical thinking".
As for the draft legal text, EU, Irish and British officials will have to start soon, probably after the March European Council, to negotiate.
Dublin says it would like to hear from the UK what detailed and legally credible solutions it has on the customs issue, and how compatible will those solutions be with the EU rule book.
In the meantime, Dublin will insist that the default "alignment" option remains embedded in the Withdrawal Treaty.