Another day, another humiliation for the Prime Minister. There's little fun in interminable ritual. When even your Attorney General says, in boomingly polite but forlorn language, that you haven't really achieved anything, the game is up.
In this tricky Cheltenham week, one odds-on certainty was the DUP saying no to Mrs May's sad effort at repackaging goods rejected in January, relaunched in February and spurned again in March.
The ERG-DUP grouping hardly needed the legal brain of Nigel Dodds in their 'Star Chamber' to declare May's amendments inadequate. A tenth-rate provincial solicitor could have done the job.
Given the certainty of her defeat last night, one might hope this is all a charade.
You cling to the hope the Prime Minister possesses Machiavellian genius, playing the long game in believing that Westminster will eventually come around to the EU/May withdrawal agreement.
This would be to overly credit her political acumen. There might never be parliamentary approval for what she proposes and time is running out for dangerous political games.
One can understand the PM's frustration. She has always been concerned to keep the border in Ireland soft and has the backing of many Northern Ireland voters, businesses and farmers.
But the ERG does not care about the border, while unionist political parties take an absolutist, political view of a predominantly economic document and Labour plays politics, because that's what parties do.
Opposition to the backstop is out of kilter with the views of many in Northern Ireland, but the DUP will not change. And May needs the DUP more than the DUP needs May.
That said, the argument from 'commentators' about the DUP 'determining the fate of the UK' (see Twitter) is bizarre. Mrs May's defeats in the Commons on her deal have been by an aggregate of 379. There have been 823 votes cast against the backstop.
The DUP would have to go forth and multiply rather a lot to provide all those votes. Nigel Dodds and his parliamentary colleagues have provided a mere 2.4% of the total votes cast against the EU plan.
In terms of defeating the backstop, the DUP is winning. If that results in a no-deal Brexit, the victory may be pyrrhic.
Sitting atop the no-deal cliff waiting to be rescued is of course, a high-risk strategy. No serious analyst thinks Northern Ireland would be economically better-off by leaving without a deal.
Even assuming there is no return to violence, acute political divisions may be further sharpened by a hardened border, psychological as well as physical.
And, according to LucidTalk's polls, the one scenario which could conceivably make a border poll very risky for unionism is a no-deal Brexit.
Few in the DUP leadership expect - or truly desire - a no-deal departure. Most within its ranks expect a softer Brexit, with Northern Ireland quitting on the same terms as the rest of the UK. And that, for the DUP, is the bottom line.
What happens next? First up will be a Commons rejection of no deal, as if passing a resolution at Westminster somehow magics away the default position - which is no deal and departure on March 29.
The EU will only grant an extension to the UK's departure date until May 24. Beyond that, the UK has to participate in European Parliament elections.
At least Northern Ireland has considerable experience of elections where those elected do not take seats. On the Northern Ireland model, the three MEPs will get paid regardless.
A stay of Brexit of two months does not a policy make. Ditto mere opposition to the backstop.
It's time for the DUP - and others, including the Labour Party, to articulate with precision and clarity their preferred mode of departing the EU. If no backstop, then what, exactly?
Jon Tonge is Professor of Politics at the University of Liverpool