The British House of Commons has witnessed some remarkable performances over the centuries, but rarely one as forlorn as the speech that Theresa May, the Conservative Prime Minister, delivered on Tuesday afternoon, before a second vote was taken on the agreement she has negotiated for Britain to leave the European Union. At the best of times, May is no great orator, and this was far from the best of times. Her voice was raspy and strained. Still, she managed to carry on for more than an hour, appealing in vain for support. “Ultimately, you have to practice the art of the possible,” she said at one point. “And I am certain that we have secured the very best changes which were available.”

As May spoke, she must have known that she was facing another humiliating defeat. The previous night, she had returned to London from Strasbourg wielding a set of documents that she claimed included some important concessions from the E.U., especially on the “backstop”—a controversial part of the Brexit agreement which would keep Northern Ireland tied to the E.U., forcing Britain to carry on abiding by many of the Union’s rules, if the two sides can’t reach a long-term trade agreement at the end of a twenty-one-month transition period . The new agreement, which May reached with Jean-Claude Juncker, the head of the European Commission, included a joint statement that the E.U. couldn’t deliberately try to keep the backstop in place by negotiating in bad faith during the transition.

To Brexit hard-liners in the Conservative Party, and to the ten M.P.s from Northern Ireland’s Democratic Unionist Party, who hold the balance of power in a closely divided chamber, the backstop—which was designed to prevent the reëmergence of a hard border between Northern Ireland and the Republic of Ireland, an E.U. member—has emerged as a key reason for their opposition to May’s deal. The Tory hard-liners claim that the backstop would prevent a clean break with Europe; the D.U.P. is worried about the future status of Northern Ireland within the U.K.

On Tuesday morning, the Prime Minister had been hoping that the concessions she had obtained would win over enough of the skeptics to pull off a surprise victory. But much hinged on an opinion from the chief legal adviser to her government, the Attorney General, Geoffrey Cox.

In a closely reasoned opinion that he read out to the Commons shortly after noon, Cox said that some of the E.U.’s concessions were significant. He also said “it is highly unlikely” that the two sides would be unable to reach a final agreement to avoid triggering the backstop. But he added that this was “a political judgment.” And he went on to say that the “legal risk” of Northern Ireland—and, by extension, the rest of the U.K.—getting stuck in the backstop “remains unchanged.” If that happened, he added, the U.K. would have “no internationally lawful means of exiting the [backstop’s] arrangements, save by agreement” with the E.U.

Shortly after Cox issued his opinion, the D.U.P. cited it in a statement saying it would vote against May’s revised deal. “It is clear that the risks remain that the UK would be unable to lawfully exit the backstop were it to be executed,” the statement said. Later in the afternoon, there was a meeting of the European Research Group, an ardently anti-E.U. faction of the Conservative Party that helped to sink the original version of May’s deal, and most of the M.P.s present indicated that they intended to defy the Prime Minister again.

That was that. With all but three members of the opposition Labour Party also opposing May’s deal, it went down by three hundred and ninety-one votes to two hundred and forty-two. The margin of defeat—a hundred and forty-nine votes—was smaller than the margin of two hundred and thirty in January’s vote, but it was another historic rout of a sitting government. Jeremy Corbyn, the leader of the Labour Party, immediately called on May to resign. Instead, she issued a statement saying that she profoundly regretted the result of the vote. She also confirmed a prior commitment to allow M.P.s to vote on Wednesday, on a motion ruling out a no-deal Brexit, and on Thursday, on a motion to put back Britain’s departure from the current date of March 29th.

And so, two years and nine months after the Brexit referendum, there is still no end to the gridlock and chaos it has induced. At this stage, May isn’t so much a busted flush as a deck of cards that has been shredded and stomped into the dust. But there is plenty of blame to go around: for David Cameron, the former Prime Minister, who cavalierly called the 2016 vote, thinking he would be able to breeze through it; for the plutocrat-owned Fleet Street newspapers that have demagogued Brexit from start to finish; for Jacob Rees-Mogg, the leader of the European Research Group, who, in the words of the Independent’s Matthew Norman, “is cocooned within the demented fantasy bubble of a post-Brexit imperial renaissance”; and even for Corbyn, who has tried to straddle the pro-Brexit sentiments of many of Labour’s working-class voters and the anti-Brexit sentiments of many of the Party’s members and M.P.s. (Corbyn’s current position is that he supports a soft Brexit, as well as a second referendum. Most of all, it appears, he wants a general election.)

What is sorely needed is some genuine leadership and a cross-party alliance to drag the country out of the mess it finds itself in. More immediately, as an editorial in Wednesday’s Financial Times pointed out, “MPs must stabilise the political situation and create the space for a Brexit rethink,” by passing the motions ruling out a no-deal Brexit and calling for an extension of Article 50. With March 29th just two weeks away, failure to do this could lead to economic chaos, gyrations in the financial markets, and a dangerous political vacuum.

“Enough is enough. This must be the last day of failed politics,” Carolyn Fairbairn, the head of Britain’s largest business group, the C.B.I., said after Tuesday night’s vote. “A new approach is needed by all parties. Jobs and livelihoods depend on it.” More than that: the future of Britain depends on it.