Ever since the start of the Brexit negotiations, diplomats and political leaders across the European continent have repeatedly insisted that the 27 surviving members must remain united behind EU Brexit negotiator Michel Barnier whenever they sit across the table from David Davis.
That unity has been never more apparent than over the past week or two, ahead of Theresa May’s meeting with EU Commission chief Jean-Claude Juncker.
Before the “crunch lunch”, Juncker’s EU Council counterpart Donald Tusk travelled to Dublin for talks, where it became clear that the EU’s position was increasingly focused on supporting the Republic of Ireland, as it sought clarity and — in some sense — concessions from the British government about a solution for its border with Northern Ireland.
But when I arrived in Dublin in late November, the country was in the throes of a full-blown political crisis, with then deputy prime minister Frances Fitzgerald under mounting pressure to resign on the back of a whistleblower scandal.
When I met Fitzgerald earlier that month, she hewed to the Irish government’s oft-repeated line that there could be no return to a hard border. She said the onus fell squarely on the British government to develop a workable solution.
But just two weeks later she tendered her resignation, allowing what looked like an intractable political crisis to pass, and the threat of an imminent election to subside.
And significantly, there was not a chink of daylight between Fitzgerald's position and those of her successor, foreign minister Simon Coveney, Prime Minister Leo Varadkar, or indeed the Irish commissioner in Brussels, Phil Hogan.
Although many of these significant players in this drama have competed with one another in the past, any resulting tension has vanished in the face of Brexit.
The UK’s departure does not just threaten Ireland’s tens of billions of dollars in goods and services.
According to many politicians I spoke to inside and out of government on both sides of the border, it also jeopardises the success of the Good Friday Agreement.
There are claims from members of the Conservative party that domestic political pressures have driven Varadkar to adopt a hardline approach when the UK hopes to conclude this phase of Brexit talks. But that was not my impression after a week’s reporting across Ireland.
Micheal Martin, the leader of the opposition party Fianna Fail, told me that he and the Prime Minister have now developed a better understanding of each other thanks to the crisis.
When I asked him if he would continue to support Varadkar’s minority government on Brexit, his answer was unequivocal. “We will of course,” he said.
As May tries to thread the needle between Brussels and her own party’s Brexiteers, she may cast a rather envious eye across the Irish Sea.
Life in Number 10 would be significantly easier if she could rely on that level of political cover from inside her own cabinet, let alone from the opposition benches.