An updated version of this article with details of David Davis’s resignation can be found here

THERESA MAY is often called weak and indecisive. Yet the prime minister belied both epithets on July 6th when she pushed her plan for a softened Brexit through an all-day meeting of her cabinet at Chequers, her official country residence. After the meeting a steely Mrs May said the days of ministerial dissent on Brexit were over. From now on, she intends to enforce collective cabinet responsibility, implying that any minister who objects publicly to her proposals will have to resign.

The full details will not emerge until a white paper is published later this week. But Downing Street has released a summary. Britain will be in a common regulatory area with the EU for all goods, including agrifoods, and will also promise to observe all future EU rules. This implies effective membership of the single market for goods. The figleaf that Parliament will have the right not to adopt EU legislation is just that; in practice, because it would mean losing unrestricted access to the single market, it will be a nuclear weapon that cannot be used.

Services will not be in the single market, however. Mrs May hopes instead to secure open trade with the EU through some system of mutual recognition, while keeping the right to vary rules to suit trade with third countries. But to satisfy Brussels, she also promises not to undercut the EU through lower standards for the environment, social and employment policies or rules against state aid. A dispute-resolution mechanism implicitly accepts a role for the European Court of Justice.

On customs, Mrs May suggests a “facilitated customs partnership” under which Britain would collect EU tariffs on imports but refund them for any that stay in Britain. But this untested scheme will not be ready for some years. In the meantime Britain will, in effect, stay in a customs union with the EU. The combination of single-market membership for goods with a customs union will preserve frictionless trade with the EU and satisfy Mrs May’s undertaking to avert a hard border in Ireland.

Hard Brexiteers were appalled by these proposals. Several agreed with the view of Martin Howe, a leading Eurosceptic lawyer, that they imply a “black hole” Brexit that turns Britain into a “vassal state” subject to EU rules while having no say in them. The customs and goods proposals will make it all but impossible to strike ambitious trade deals with third countries. The chances of a trade deal with America will be tiny despite Donald Trump’s apparent enthusiasm for one; Mrs May’s plan precludes the acceptance of American agrifoods, a priority for negotiators there. And the exclusion of services, which make up 80% of the economy and in which, unlike goods, Britain has a large trade surplus, seems better for the EU than for the United Kingdom.

Yet Brexiteers have long known that Mrs May and her advisers were moving towards a softer Brexit. Boris Johnson, the foreign secretary, reportedly likened her proposals at Chequers to “polishing a turd”. Several Tory backbenchers were similarly critical. But the truth is that the hard Brexiteers, although freely critical of Mrs May, have not offered any other way to satisfy the demands of British business to keep frictionless trade and to prevent a hard border in Ireland. And despite many threats to do so, not a single minister has resigned.

It remains to be seen how Tory backbenchers will respond. Some hardliners talk of staging a leadership challenge to Mrs May, which requires the nod from just 48 Tory MPs. But they must know they are unlikely to win any contest. Michael Gove, the pro-Brexit environment secretary, conceded on July 8th that the parliamentary arithmetic since the June 2017 election had made a softer Brexit inevitable. He now places his hopes on the notion that, after Brexit has happened next March, its terms can subsequently be changed.

That will be difficult. Mrs May intends to enshrine her proposals in a treaty. Even so, there is a clearer route to a harder Brexit: that the EU rejects her plan out of hand. European leaders have made clear that they cannot accept cherry-picking in which Britain takes the benefits it wants from the single market without accepting all its obligations. But since Mrs May’s white paper will be the first full proposal that Britain has made since the June 2016 referendum, EU leaders are likely to agree to study it carefully and then be ready to negotiate over its details.

This is where problems may arise. Mrs May thinks her softening of Brexit is as far as she can go politically. But EU leaders will want a lot more, including continuing payments into the EU budget. Trickiest of all, they are likely to demand an acceptance of the principle of free movement of EU citizens, which they see as one of the four indivisible freedoms of the single market. Mrs May was firm this week that free movement will end, though she is offering a “mobility framework” in its place. Unless this is sufficiently generous, however, the EU will still probably say no.

Some Brexiteers hope that, in that event, they can resurrect the idea of walking out with no deal at all. In a sop to them, the cabinet has agreed to step up preparations for such an outcome. But in practice, it is too late. A no-deal Brexit next March would have catastrophic consequences for the economy. Some form of Mrs May’s softer Brexit is likely to prevail. Brexiteers have only themselves to blame. In over two years since they won the referendum, they have failed to come up with a convincing and workable alternative.