During the second day of debate on Theresa May's Brexit deal on Wednesday, the SNP's Joanna Cherry compared Scotland's voice in the negotiations with Ireland's.
The union that is the United Kingdom ignored Scotland as it pursued Brexit, she said, and sought to ignore the concerns of Ireland, North and South.
“However, because the EU27 got behind the Irish Government’s legitimate concerns, they became central to the Brexit process. Conservative politicians – not all of them, but some – and indeed a few on the benches behind me, waited in vain for the EU27 to crack and throw Ireland under the bus. That did not happen, and it is not going to happen,” she said.
She cited a remark by Mary Daly, professor of history at University College Dublin, that the current situation had uncanny echoes of what happened here 100 years ago "when the electric politics of Ulster determined what happened at Westminster".
The title of Daly's most celebrated book The Slow Failure describes the likely fate of the prime minister's Brexit deal as MPs debate it for a further 24 hours over three days. The politics of Northern Ireland and the backstop look set to sink the deal in next week's vote, with up to 100 Conservative MPs threatening to oppose it.
The attorney general's legal advice on the deal, published in full on Wednesday, revealed nothing new about the backstop but it described the reality in stark terms. It was clear that Britain could not leave unilaterally and that Northern Ireland would have to treat the rest of the UK as a "third country" where goods regulation was concerned.
The prime minister promised MPs on Tuesday and again on Wednesday that she would look at ways of addressing their concerns about the backstop. But she has ruled out attempting to reopen the text of the withdrawal agreement and neither Brussels nor Dublin will offer any concessions ahead of the vote to help her win it.
A "parliamentary lock" to give MPs a vote ahead of entering the backstop would not win over enough Brexiteers to win the vote and it risks accusations of bad faith from the EU. But the prime minister's aim now is to reduce the margin of defeat so that she can return to Brussels to seek a concession from the EU.
Even if she survives next week’s vote and can argue that her Brexit deal is still viable, EU leaders are unlikely to offer any immediate concessions. But if she is still in place in January and there is a chance to save the deal, the EU’s solidarity with Ireland so envied by Cherry will be put to the test.