When we last asked our Party members’ panel for a view of Theresa May’s Chequers plan, two in three respondents opposed it.  We will soon report their latest take from this month’s survey.  But a large slice of Tory activists, and enough Conservative MPs to run easily into double figures, have clearly set themselves against Chequers – as today’s papers remind us.  Boris Johnson fires up his cannonade against it in today’s Daily Telegraph.  Steve Baker is in place to help organise the scheme’s opponents.  David Davis is free on the backbenches to speak and vote as he pleases.  In a Commons in which the Government has no majority, all this counts.

Furthermore, the Prime Minister has not explained why her Brexit policy on goods, plus agri-food, has shifted from one based on “a comprehensive system of mutual recognition”, as set in her Mansion House speech earlier this year and previously, to one based on a common rulebook and regulatory harmonisation.  “I will not be pushed into accepting compromises on the Chequers proposals that are not in our national interest,” he wrote in yesterday’s Sunday Telegraph.  Many party members will read that as: more concessions coming.

There is a trust and values issue.  On trust, they are uneasy about what they see as a May-Robbins duopoly that now drives Brexit policy.  On values, the handling of the Boris Johnson burka row highlighted the gulf between what what the elites and the voters think – and that the Tory reaction was led from CCHQ rather than Downing Street will have been missed by many activists. In short, the instinct of many members, when mulling Chequers, is to think with their guts.  They yearn to tear down the pillars of the Prime Minister’s new temple.

We share the impulse. But Tory MPs returning to the Commons this week need to use their heads as well as their hearts as they weigh what to do next.  Their starting-point will be that Chequers is clearly not acceptable to the EU as it stands.  The European Commission prefers a tried-and-trusted model.  The one most consistent with the Conservative Manifesto is a Canada-style scheme such as that set out in the Government’s own “Alternative White Paper” proposals drawn up by David Davis and published on this site.

The European Research Group, a revitalised Change Britain, the new Stand Up 4 Brexit operation and a re-engaged Lynton Crosby have joined forces to press for such a scheme.  Mark Wallace has set out on this site why the UK-Ireland land border is not an insuperable obstable to this plan (though a maximum facilitation customs scheme that avoids border checks is very unlikely to be ready by 2022).  The EU could conceivably come to see that it is worth dropping December’s backstop to gain a Canada-type settlement.

Tory MPs should push for this as EU resistance to Chequers intensifies.  But there is a snag.  There will be no Commons vote on a Canada Plus Plus Plus trade deal. Nor will there be one on a Chequers-inspired trade deal, either.  Rather, if an agreement is reached, MPs will vote on two items: a Withdrawal Agreement and “the future relationship”.  The first will be precise.  The second will be vague – a general declaration of aims and ambitions, based on Chequers or just possibly on Canada or some other model.

If such a point is reached, the cry will go up that May proposes to give the EU some £40 billion of taxpayers’ money and get nothing bankable in return.  Worse still, some will say, the backstop agreed last December will be in place – with the threat that it poses to the integrity of the United Kingdom.  The simplest course for Conservative MPs to take in response would be to vote the plan down, especially if it is based on Chequers with the further concessions to the EU which will doubtless come.  What would follow?

There are reports that Downing Street is mulling calling an election in such circumstances.  The Fixed Terms Act would be no more impassable an obstacle to this than it proved to be to last summer’s poll.  None the less, the Tory Parliamentary Party is set against an election.  Conservative MPs have been scarred by last summer’s setback.  It is far from certain that the Cabinet would let the Prime Minister take a gamble that could turn her out of Number Ten and put Jeremy Corbyn in.

Indeed, it is hard to see how she could survive the defeat of a deal on which she had staked her authority.  But there is far more at stake even than the fate of the Prime Minister.  A range of possibilities would follow the rejection of her agreement, whether by means of the “meaningful vote” or some other device.  At one end of the spectrum is No Deal.  At the other is No Brexit – that’s to say, the Government or the Commons or both postponing the movement of Article 50 with the EU’s agreement.

The optimistic case for No Deal is that side-deals make it manageable; that legal difficulties would manifest themselves less in practice than on paper; that a falling pound would make up for new tariff and non-tariff barriers; that Britain’s sturdy growth, strong employment and improving public finances would see us through; and that the Government, with its new freedom to diverge from the EU norms, would cut tax, slash regulation, control immigration and strike the new trade deals which are an integral part of a new post-Brexit settlement.

The pessimistic case relies less on the Project Fear Two Remainer scare stories of this summer than on sober calcuation.  The Government has published no immigration plan.  It has agreed no customs plan.  Its stress on transition has left it ill-prepared.  If No Deal is a cats-cradle of preparation, diplomacy, law and a time shortage, the danger is that Britain gets tangled up it.  Dominic Raab conceded amidst the recent release of technical announcements that while we can control our own preparations, we cannot control the EU’s.

Rationality and mutual interest would doubtless assert themselves sooner or later.  The question is how long that would take – and whether any interim, with stalled investment, lost jobs and a possible recession would offer Jeremy Corbyn the electoral breakthrough that has eluded him to date.  The Government has itself ruled out some of the regulatory changes that enthusiasts for a Singapore-style Britain would like to see.  There isn’t a Commons majority for radical change in any event.

We look forward to Raab publishing more details of the Government’s preparations for No Deal, to a full pre-Party Conference assessment from the ERG (and from others who take a different view, such as Britain in a Changing Europe), and to the forthcoming take from Open Europe.  All this will help make the landscape clearer.  On the postponement of Article 50, the calculation is simple, but not easy.  Some Brexiteers argue that, with the EU Withdrawal Bill now in place, no Government will have the Parliamentary time to stall or dump Brexit.

They may be right.  But MPs voted Remain by roughly 480 to 184.  The Commons has not fundamentally changed since.  Can we really be so sure that, amidst what would be presented as an even more convulsive crisis than Suez, the Government might fold – or the legislature itself grab control of the wheel?  The ironic possibility lingers that chucking Chequers might break Brexit.  Yesterday, Nick Boles supported an alternative to either No Deal or a Bad Deal – the EEA port-in-a-storm option. Today, George Trefgarne joins him.

We will explore it in a series on ConservativeHome this week that will set out some of the pluses and minuses.  The latter include some formidable political difficulties and risks.  The most straightforward course for Conservative MPs and members to take – enraged as some are by Chequers; distrustful as many are of the Prime Minister, and frustrated as nearly all are by the negotiation – is to damn the complexities, keep it simple and resolve now to vote down any deal based on May’s current plan.

If you believe that the race to the Brexit winning line is a sprint, deciding to do so makes sense.  But Brexit is a marathon, goodness knows, not a dash.  It requires using heads as well as hearts, so simply opposing Chequers is not enough.  We wish Tory MPs well in their exercise of both during the weeks and months ahead.  One fundamental shines through.  By whatever means, the referendum result must be honoured.  The race must be run.