No prime minister likes to lose in parliament. Theresa May must be getting used to it. On Tuesday night she was defeated for the 18th time in her short premiership. Crucially she lost, once again, the “meaningful vote” on her deal to leave the European Union, though it was by a smaller margin than the record defeat she suffered in January. Mrs May’s inability to secure a majority for her withdrawal agreement suggests that her command over parliament is evaporating. There is virtually no chance that she can push through the agreement before Britain is due to leave the bloc on 29 March.

Mrs May anticipated this dismal scenario. She will now hold a parliamentary vote on whether MPs want to leave the EU without a deal – a damaging, disorderly Brexit. So weakened is the prime minister that her authority does not even extend to the cabinet table, forcing her to give a free vote on whether or not to back a hard Brexit. That cabinet ministers would vote to transform the current political and constitutional crisis into an economic one for the sake of their careers shows how deeply corrupting Brexit is. A no-deal Brexit needs to be voted down to stop ruinous fantasies taking hold in our politics.

What Mrs May will then offer is a vote on whether to seek an extension from European partners, which opens the doors for MPs to redefine the terms of our exit from the EU. If such a delay – short enough to ensure the UK is not involved in European elections – materialises, Mrs May will offer the Commons a choice between her retweaked deal and a chaotic no-deal Brexit that MPs ought to have already rejected. This would be the wrong course for Mrs May to take. If the record scale of the opposition to her Brexit deal in January was unable to gain any significant changes from EU counterparts on the Irish backstop insurance policy then it is unclear what will be achieved in another two months. Mrs May got to this point through errors of diplomacy, governing style and domestic political strategy. MPs should vote for a delay, but one that is longer than the respite Mrs May desires. It would be practical, since the European Union will be consumed by elections and recomposing the commission between May and October. Such a postponement ought to give relief to UK businesses suffering from the current uncertainty.

If it was simply a way of buying time and extending the impasse, it is less clear whether the EU would accede to any request. The prime minister said she wanted to “learn the lessons” of the first phase of Brexit and “build consensus” for the next phase. Mrs May can only do this by having an honest conversation with the public about what sort of future relationship with the EU they can unite behind. This is what she had conspicuously failed to do, employing harsh nationalistic language to ensure her own political survival, which alienated both MPs and European partners. The prime minister sowed the seeds of her downfall by making the reduction of immigration, fantasy free-trade deals and withdrawal from the European court of justice as her priorities. It was her refusal to regard as legitimate the interests of the 48% who voted to remain which signalled that Mrs May would deepen the divides that the referendum campaign had opened up.

The Brexit division is not one that can be overcome easily through argument – but it could have been. Instead Mrs May helped to make the division between leavers and remainers about identity and morality. Such a politics will take time to unwind. A longer delay is necessary because politicians have to realise that they must stop surfing the tidal wave of populist nationalism for electoral success when the tsunami could smash society.

A delay ought to be long enough to allow the UK to contemplate what Brexit means for this country, rather than being hustled out of the door by a Conservative party on the verge of a nervous breakdown. A pause is required because a pivot to a new arrangement is easier said than done. Most of the proposed alternatives to our membership of the EU have, under Mrs May, seemed unattainable, unappealing or both. For the UK to be in a better place politically will require a different, better politics. That will take time, and Mrs May needs to ask Europe for it.