Theresa May emerged from her five hour cabinet meeting yesterday evening looking like she’d given up. She couldn’t muster any enthusiasm for the deal she’d just pushed through a fractious cabinet, describing it as one might an unwanted birthday gift – not ‘good’, just the best she could get. Her speech indicated the way the government is attempting to spin the agreement: that passing the deal through the Commons is in the ‘national interest’, and the only safe way between the Scylla of ‘no deal’ and the Charybdis of ‘no Brexit’. Effectively, this is legislative Project Fear – unable to defend the deal in its own terms, the government will rely on the threat of doom to attempt to grease its passage. With the Brexit secretary, Dominic Raab, resigning this morning, the deal and her government is imperilled.

There are serious defects in the agreement as it stands: it is effectively a reversal of the government’s former position that ‘no deal is better than a bad deal’. The EU’s negotiating team has always been obsessed with a ‘level playing field’, meaning, in effect, alignment between the EU and UK’s economic common sense – the agreement as it stands represents a serious victory for their negotiators. It binds the UK to environmental targets, European tax regulations, and stringent state aid rules – as well as enshrining the supremacy of the EU’s Court of Justice (CJEU) in the UK’s immediate post-Brexit legal environment.

Three groups of MPs will be especially motivated to reject the agreement. First, various factions of the pro-Brexit Tories: with Raab, Esther McVey (and likely more) exiting the government today, their opposition to the proposed deal is clear. For them, the bilateral clauses on the Northern Ireland backstop (allowing the UK to withdraw only with mutual agreement of the EU), the expansive role of the CJEU, and the non-regression clauses on workers’ rights and environmental regulations would shatter their vision of a Singapore-style, unbridled capitalist Britain. Additionally, trade clauses in the the protocol on Northern Ireland would restrict the ability of a post-Brexit UK to undercut the EU on external tariffs – which effectively vitiates trade secretary Liam Fox’s dreams of repositioning the UK in the global market.

Second, the DUP: it is abundantly clear that the Northern Ireland protocol runs through the Unionists’ red lines. In order to avoid a hard border in Ireland, it is likely, under the agreement as it stands, that Britain will impose some form of customs check effectively in the Irish sea, with the UK as a whole existing in a customs ‘grey zone’. This is something the DUP will never vote for. But this issue is a live problem for Scottish Conservatives and the SNP as well: as Nicola Sturgeon made clear last night, Scotland will be deeply anxious about any deal which makes Northern Ireland a special economic zone, more attractive for EU-wide capital than a hobbled Scotland subject to more stringent rules. And so restive a Scottish politics is likely to make Westminster anxious.

Third, the Labour party: Jeremy Corbyn’s speech in parliament today makes clear that the leadership of the Labour party regards the agreement as transgressing the party’s six Brexit tests, and will therefore reject any attempt to pass it through parliament. Especially concerning for the party’s left – and thus its leadership – will be the commitments in the agreement to retaining all of the EU’s rules against ‘state aid’, including continued alignment with any further regulations the Union makes in this area. Not only will this concern those who see the EU’s Fourth Railway Package as a threat to any attempt to bring rail back into public ownership, but also leaves an ominous question mark against Labour’s plans for wider expansion of ownership of public goods. Even for those who believe or hope reforms could be achieved in the EU to allow such policy, an agreement which sees Britain align with future European rules without a voice ought to give them pause. Certainly Michel Barnier’s insistence on the inclusion of these clauses in the agreement is on one level a precautionary move against the possibility of a future left government in Britain.

Such political terrain makes it extremely unlikely May’s agreement will pass through parliament – it is unclear, at the time of writing, that May herself will endure much longer – so what is next? It is possible, should May survive long enough to bring the agreement before parliament, it will ramp up Project Fear, and develop May’s rhetoric in front of No. 10 yesterday to paint the Labour party as working to frustrate Brexit. Though a vote to bring down the government via the Fixed Term Parliaments Act is still extremely unlikely, it is much more probable that an intra-Tory coup via the 1922 committee would succeed in removing May from office. In such a scenario – with the PM’s authority shattered, and a shoal of Brexiteer minnows vying for power – the deal is dead.

Too often commentary on Brexit forgets that the negotiation is not inside the British parliament, but with the EU27. Michel Barnier has made clear that the Union, absent ‘exceptional’ political change in the UK – a change in government, or a second referendum – he considers an extension of Article 50, or renegotiation, unlikely. The political options therefore look as follows: a government of national unity, a second referendum, or a general election. Anna Soubry – the famed unrebellious Tory ‘rebel’ – has called for a unity government. Such a government – with Labour propping up the chaos at the heart of the Tory administration – would effectively mean Labour signing an electoral death warrant. A second referendum requires several hurdles which, though not impassable, seem extremely taxing: legislative passage under the Act governing referendums in parliament; the formulation of an appropriate referendum question; concession on the part of the EU for sufficient time to conduct the exercise. It is possible that such a referendum would offer no clearer direction, and no more significant a majority, than 2016’s vote. What then?

The third option is a general election. Without the fixed-term Act passed to shore up the Cameron-Clegg coalition, such an election would already be underway; it is the natural remedy for political impasse. An election allows not only a conversation about Brexit in narrow technical terms, but to put to the country the profoundly differing visions of the future which now exist between the two major parties, including a throughgoing rejection of Conservative economics, a rebalancing of the country’s disgorged financial sector, and an end to the punitive austerity of the past Tory administrations. Such an election would be difficult for Labour: it would require the party to clarify its Brexit plans beyond the six tests, in explicit propositional terms, and require a future Labour government to push for renegotiation under an extended Article 50, in order to rectify the mess and incompetence of the Tory negotiating team. This seems the best strategy for the left in Labour: it will require those active in the party to demand their MPs refuse Tory fear-mongering and the siren call of Soubry’s national government.

As we enter what looks like the endgame of May’s ministry, the sights of the left ought to be focused on the possibility of a transformational, socialist government. Behind the political churn, deep questions lurk: what sovereignty looks like in a globalised world, how to rectify the decades of wreckage inflicted by successive governments on this country and its working class, how to adequately tackle the planetary death spiral capitalism has locked us into. Only the left can answer those questions – and it now must.