UNTIL two weeks ago, Dominic Raab was the Cabinet minister with responsibility for negotiating Britain's exit from the European Union. On Friday, he said that leaving the EU under his own Prime Minister's Withdrawal Agreement “would be even worse than remaining in the European Union”. Well, precisely. Unfortunately, he didn’t draw the obvious conclusion: that we’d be better off staying in.

Brexit is in danger of becoming a dead parrot. In his BBC interview Raab pointedly refused to endorse Theresa May's mantra “no deal is better than a bad deal”. And the Prime Minister is not saying that any more either. If no deal is out and the PM's Withdrawal Agreement is toast, it means Brexit is now seriously stalled. This opens the way for the entire process to be halted, if an when parliament rejects the May deal emphatically and finally, as it must next month.

Yet at the beginning of the week, it rather looked as if Theresa May was going to succeed in delivering her Chequers-derived exit deal. So what happened? Two events led up to this important juncture: the failed “Dad's Army” coup and the publication of the Political Declaration.

The vainglorious attempt by the European Research Group of hard Brexit Tory MPs, led by Jacob Rees Mogg, to organise a coup against the Prime Minister was a dismal failure. They failed to gather enough votes even for a leadership contest to be triggered. It exposed the entire hard Brexit faction of the Conservative Party to ridicule and underlined their own irrelevance. Strike one to Theresa May.

Suddenly, the press started to feature more positive images of the PM: no longer the hapless, bumbling dancing queen but a serious politician doing her best, a stateswoman even. One Tory backbench supporter said her opponents were motivated by “misogyny” and many women appeared to agree. A YouGov/Times polls showed that the PM's approval rating had risen 13 points in one week.

But then came what was probably the crunch moment in the entire two and a half years of Brexit negotiations: the publication of the 26 page Political Declaration. This was supposed to outline Britain’s future trading relations with the EU after Brexit. It didn’t. The painful reality is that nothing has been agreed.

To say that the document is woolly is an insult to sheep. It is a disingenuous confection of warm words, empty declarations and wishful thinking that no one could possibly take seriously. The only thing it really delivered was a surfeit of adjectives - “ambitious, broad, deep and flexible” - without the slightest hint of how Mrs May's “frictionless” trade deal could ever be achieved. It amounted, as the First Minister Nicola Sturgeon observed, to the release of a herd of unicorns.

Theresa May insists that the PD outlines “a unique trading relationship” with the EU, but it does nothing of the kind. It promises: “a free trade area as well as wider sectoral cooperation where it is in the mutual interest of both Parties.” But the reality is that the mutual interests of the parties, the UK and the EU, are irreconcilably opposed, not least because of the PM’s red lines on immigration and the single market. At bottom, the Political Declaration only guarantees a Canada-style free trade agreement.

The document makes clear that the EU will regard the UK as a “third country”, and that further participation by the UK in the single market involves: “respecting the integrity of the Union’s Single Market and the Customs Union and the indivisibility of the four freedoms”. If Britain accepts the common rules or “level playing field” on trade and services, it has also to accept “the integrity of the Union’s legal order... including the role of the Court of Justice of the European Union (CJEU) in the interpretation of Union law”.

This has been compared to the kind of control the old Soviet Union exercised over nominally autonomous republics like the Ukraine. That's unfair: the EU is not a communist dictatorship. But it does look very like the current EU arrangement with Turkey, which is in the Customs Union for goods but not in the EU. This is because of Britain's commitment to the Northern Irish backstop in the draft Withdrawal Agreement, which accompanies the Political Declaration.

The backstop began life as an attempt to prevent a hard border in Northern Ireland, but has ended up placing the UK in an intolerable position for a sovereign nation: having to accept laws over which it has no control. Dominic Raab is absolutely right. This is far worse than remaining in the European Union. Right now, the UK is fully represented, not just in the EU parliament and the Brussels commission, but as a member of the Council of Ministers, is part of the supreme decision-making body of the Union. This gives the UK an effective veto matters of vital national interest.

Britain loses this power next March, when we leave the EU. Thereafter we will still have to accept EU laws during the transition period and throughout the backstop arrangement, which will continue unless and until there is a new frictionless trade deal negotiated. The Political Declaration made clear that there isn't the remotest sign of such a deal happening.

In the backstop, Theresa May has agreed for the UK to remain in the Customs Union (or “territory”) and for Northern Ireland to remain largely in the single market. Worse still, Britain can only leave the backstop by mutual agreement with the EU, which gives Brussels an effective veto on Britain’s departure from it. As Dr Kirsty Hughes has pointed out, the transition/backstop places the UK in the same subordinate position as Turkey, a country which is trying to enter the EU but has not met the relevant conditions. Britain will have a legal obligation to follow trading rules on which it has no say.

Does Theresa May understand how the EU functions? She says that Britain is restoring its “sovereignty” in the Withdrawal Agreement. Yet the truth is, the UK never lost its sovereignty in the 45 years it was in the EU. This was stated clearly in paragraph 2.1 of the UK government's own White Paper in February 2017. However, under the Withdrawal Agreement Britain really does stand to lose sovereignty, and become a country whose laws governing trade are set by a foreign entity.

That 585 page document was a tightly-drafted legal text, written in a language accessible only to lawyers. Now the Political Declaration has, by its very vagueness, exposed Britain's dilemma with crystal clarity: we are in danger of making a mistake of historic proportions. It is simply impossible to contemplate Britain agreeing to this, and no responsible national legislature should accept it. No longer is British sovereignty “pooled” in the EU, it is effectively relinquished.

I don't blame Brussels for this. They wish Britain well, but their priority has always been to protect the integrity of the European Single Market while avoiding a hard border in Ireland. The EU negotiator, Michel Barnier, simply stuck to his brief. Theresa May tied herself in linguistic contortions, trying to gain privileged access to the EU without being a member of it. That was never going to happen. Like M.C. Escher’s impossible staircase, the negotiations always ended up at the beginning.

MPs must now help Dominic Raab to draw the obvious conclusion, revoke Article 50 and halt the process. Dead. Say no to no say.