The Conservative party was happy with Brexit, but not for long. A deal that was great in 2019 is now not great. What could fix it? What change would bring enduring satisfaction? The answer is obvious to anyone familiar with the patterns of English Euroscepticism – nothing. There is no concession big enough, no deal good enough, just as no single fix can end the cravings of a drug addict. The long-term solution is to get sober. That is not on Liz Truss’s agenda. On Tuesday, the foreign secretary informed parliament of a government plan to assert its own version of the Northern Ireland protocol. That is a threat designed to prod the EU into renegotiating the 2019 withdrawal agreement, which was itself the outcome of a renegotiation made necessary because Theresa May had done a deal that Conservative MPs also didn’t like. One reason continental leaders don’t want to talk about changes amounting to a new treaty is their certain knowledge that the Tories would be dissatisfied again soon enough. Another reason is that a revised deal would involve trusting Boris Johnson, which EU governments have done before and which no one does twice. Truss’s account of the problem in Northern Ireland elides frustration with border checks across the Irish sea and a wider complaint about the residue of EU jurisdiction in Northern Ireland that Brexit hardliners see as a stain on UK sovereignty. She is egged on by Tory backbenchers who are convinced that the protocol was foisted on Britain; that it amounts to a regulatory land-grab and that its provisions are applied with pernickety spite as punishment by Brussels of an ex-colony that had the temerity to break free. Believing that version of events requires two psychological traits that come easily to the fervent Eurosceptic. One is a capacity to forget that every problem currently associated with Brexit, including the specific danger in Northern Ireland, was signalled by remainers and dismissed with contempt as scaremongering by leavers. The other is a need to still feel victimised by Brussels even after leaving the EU, since ending that ordeal removes any excuse for Brexit not delivering its promised bounties. That is the addiction – the sadomasochistic compulsion to be oppressed by foreigners for fear of taking responsibility for the consequences of liberation. It is true that customs checks in the Irish Sea are a symbolic injury to unionist feeling in Northern Ireland. But it is also true that Johnson knowingly inflicted that injury, denied he had done it, then whipped the grievance up when he should have been hosing it down. A constitutional crisis at Stormont was not prefigured in the letter of the protocol, but it was made likely by the prime minister’s irresponsible and negligent handling of the politics of the protocol from the day he signed it. Meanwhile, if Tory backbenchers had not found all the resentment they needed in Northern Ireland, they would have gone hunting for reasons to be dissatisfied with Brexit in England instead. One of Johnson’s complaints about an Irish Sea border, as expressed in an interview earlier this week, was that regulatory checks create “extra barriers to trade and burdens on business.” That generates “a great deal of faff and botheration”, which increases living costs. Those barriers are uniquely upsetting to Northern Ireland unionists on the level of national identity, but the faff and botheration incur costs also at Dover, Grimsby, Felixstowe; any place where goods move between Britain and the EU. In other words, the prime minister’s economic rationale for wanting to fix the Northern Ireland protocol contains a complaint about conditions that are intrinsic to the Brexit model he chose. That is yet another reason why no one in Brussels wants to reopen the 2019 deal. The negotiation would founder on first principles. Brussels says that if Britain is no longer automatically applying EU rules, it must prove that its exports comply. The Brexit ultras think that Brussels is only imposing that requirement out of petty vindictiveness and that the very Britishness of British standards should be sufficient guarantee of quality. That has been the impasse in every chilly phone call and deadlocked meeting between the two sides since 2016. The Tories cannot budge on that point because doing so would involve accepting two indisputable facts about Brexit. First, exiting the single market was bad for UK businesses (and the losses are not made up by free-trade deals with other countries). Second, Britain had the levers to steer EU policy as a member state and surrendered that power when it left. No minister serving in the current cabinet can admit those truths. Until that changes, UK policy towards the EU will amount to little more than rattling the cage of delusion that Brexit imposes on its believers. Some Eurosceptics find perverse pleasure in captivity, but that is their fetish and not something anyone else needs to indulge. When policies fail on such a Titanic scale, it is usual to have some debate about a change of direction. That isn’t happening, because the opposition has no alternative destination in mind, or none that it advertises in public. Keir Starmer is mindful that his support for a second referendum back in the day is still a vulnerability in constituencies where the Tories want to drive Brexit ever deeper as a wedge between Labour and its estranged core voters. One function of Truss’s bill overriding the Northern Ireland protocol is that anyone opposing it can be cast as an unrepentant remainer. Labour’s absence from the conversation is not only metaphorical. Two opposition seats on the European scrutiny committee, which notionally holds the government to account on EU matters, are effectively vacant because the Labour MPs who sat there have moved on to frontbench jobs, and haven’t been replaced. Labour strategists take the view that sanity in EU policy only becomes available by winning an election fought on other issues – things voters actually care about – and not by dancing to a drum that Johnson beats to distract from all his other failures. That is probably true. But it means the parameters of Brexit debate are set by marginal differences between maniacs and hardliners over the optimal pace for fleeing reality. It is a formula for perpetual crisis. The constitutional mess that Johnson has made of Northern Ireland is so far the gravest episode, but unlikely to be the last. The problem isn’t that the protocol cannot be made to work as written, but that it was written to enact a Brexit that doesn’t work. Rafael Behr is a Guardian columnist