The Guardian view on the Brexit vote: bin this bad deal

“Brexit means Brexit”, Theresa May’s catchphrase, helped the former prime minister navigate a profound political problem: there was no model of a future relationship with the EU that could satisfy all leave voters, and none was specified on the 2016 ballot paper.

The meaning of Brexit then evolved over three years, eventually becoming the deal that Boris Johnson has placed before parliament. This definition is a shrivelled facsimile of the product that was offered by the leave campaign. Pro-Brexit politicians never confronted the trade-offs involved in severing European ties that have developed over four decades. Instead, they dissembled and deceived, wielding the referendum result as a bludgeon to stifle debate.

The result is a final settlement shaped by two fixations: Mrs May’s obsession with immigration and the hardline Conservative Eurosceptic allergy to anything that would get in the way of a free-trade agreement with the US. Those criteria required burning any bridges to the EU’s single market and customs union. To win the Tory leadership, Mr Johnson indulged the view that Brexit by any softer definition was tantamount to treason.

Thus has a long campaign of anti-Brussels radicalisation come to fruition. The very definition of Eurosceptic has changed since the mid-1990s, when it implied resistance to closer integration alongside acceptance that EU membership had intrinsic economic value. Now only total rupture is acceptable.

In pursuit of that goal, every notion of political pluralism, moderation and economic rationality has been jettisoned. Principle plays no part in Mr Johnson’s calculation. He once insisted that a customs border in the Irish Sea would fracture the union. But when that border was set as the price for taking mainland Britain out of the customs union, he abandoned his unionist allies, leaving Northern Ireland under EU economic jurisdiction. To gratify a nostalgic fantasy born of English nationalism, Mr Johnson has struck a deal that will make the country poorer by cutting it off from its closest trading partners.

The only merit in the deal is that it would cause less immediate harm than leaving with no deal at all. Avoiding that scenario, and fatigue from the whole cursed business, will motivate many MPs to support the government today. But those are dismal reasons. Legal protection against no deal exists in the Benn Act. Any MP who validates Mr Johnson’s Brexit model, knowing it will harm their constituents, would be in dereliction of their duty.

There is a tension between rejection of a Brexit deal and the democratic imperative of respecting the referendum. The solution is to procure a mandate for this version of Brexit. The concept has mutated through three years of Conservative ideological mania. It has been refined in negotiation, culminating in a desperate dash for the finish line by a prime minister who has no national mandate of his own.

The test of this or any deal’s merit is not whether it is preferable to the worst outcome, but how faithfully it satisfies the initial promise of Brexit. The benchmark is a comparison with the benefits of EU membership. If, in 2016, anyone had described the leave option in terms identical to the deal now on offer, Mr Johnson would have called it fear-mongering and defeatism. Yet now it is his prized accomplishment.

There is now an answer to the question of what Brexit means and its cheerleaders are justly afraid to subject it to scrutiny. Mr Johnson’s plan is to railroad his deal through parliament with the aid of MPs who simply want to declare that the deed is done. But to acquiesce in that subterfuge, without due diligence, is not an exercise in democracy. It is easy to see how the prime minister’s interests would be served, but not the interests of the country.

Brexit is a choice that will reverberate for generations. It requires informed consent from those who must live with the consequences. If leavers are so confident that their project still meets the test of public support they should not be afraid to present it for ratification at the ballot box. It is time the people themselves were included in the decision.