Nick Hargrave is a former Downing Street special adviser, where he worked under both David Cameron and Theresa May. He now works at Portland, the communications consultancy.

I am so bored of the debate on Brexit that I want to scream. I am frustrated at its stultifying circularity, concerned about how it steals oxygen from other pressing priorities – and angry that it is dividing my party. I just want it be done, implemented – and for the country to move on. Apart from the real obsessives, I suspect this sentiment is true for most people in the Conservative family. It’s certainly true, as all evidence suggests, in the wider country.

Against this backdrop, it is tempting to suggest that – should the Withdrawal Agreement eventually pass and the current Prime Minister move to departure – we get swiftly back onto the domestic agenda in the next leadership contest. That we move on. I sympathise with the sentiment. Indeed, I have argued it before myself. But while this would certainly be uplifting for the country, not to mention convenient for the candidates involved, I have now come to the reluctant conclusion that we are going to have to bang on about Europe for a short while longer.

It is important to do this if our party has any hope of closure in the long-run. To be able to move on and focus proper attention on the things we really came into politics to do, the candidates must first articulate an honest and platitude free vision of our new relationship with the European Union. And critically, I believe the winner must then seek a mandate from the country in a general election shortly after.

The current Political Declaration, that outlines our proposed future relationship with Europe, does not win many awards for specificity. It is not a legal text. As George Bridges has perhaps articulated best, we have not yet made the strategic decision about the sort of country we want to be after we leave the European Union. Whether we prioritise trade with our nearest and largest commercial bloc, or whether we prioritise Parliamentary sovereignty.

Following the visceral reaction to the Chequers plan (once a term of abuse, but now barely muttered), the urgent crowded out the important as attention focussed on the Withdrawal Agreement. But with all the best will in the world, it will not be possible to gloss over these arguments once future trade negotiations begin. Trade negotiations themselves are boring and technical. What will be front page news is the internal disagreements within the Conservative tribe that have been parked, but not decisively settled.

Many of those who voted Leave see control of trade policy as essential for leaving the European Union to be a success. Others from both sides of the original referendum divide see frictionless trade with the EU as essential to manufacturing jobs and dealing with the Northern Irish border. The Political Declaration envisages the use of “all available facilitative arrangements and technologies, in full respect of their legal orders and ensuring that customs authorities are able to protect the Parties’ respective financial interests and enforce public policies”. It is highly questionable whether any of this will be practical, negotiable or legal. This is why people care so much about the arcane backstop and our ability to countenance a similar “no deal” situation in a couple of years’ time.

Similarly, on immigration policy you can expect plenty of interpretation down the road. It will be interesting to see whether the EU wishes to invoke the sentiment of Chequers about a “mobility framework” that was eventually watered down in the Political Declaration.

Trade deals beyond the EU are worth considering briefly, too. It is uncontroversial to talk rhetorically about getting out into the world and signing new free trade deals with other countries. Irrespective of whether this is commensurate with our expectations of goods trade with the EU, the trade-offs involved for independent market access with tiger economies such as China and India will be significantly bumpier in reality.

These are just a few of  the salient points that are going to occupy debate amongst Conservatives in the next couple of years. A substantial reason why we have got into the current state of affairs on the Withdrawal Agreement is that this Prime Minister was not honest about the inevitable trade-offs soon enough. Early statements of intent at the Conservative Party conference in 2016 and Lancaster House in January 2017 did not match with reality.

What is more the ‘Brexit election’ of June 2017 was anything but. As someone who sat in Conservative Campaign Headquarters during that miserable experience, I remember how we sloganised day after day about the negotiations but proactively avoided any serious discussion on the campaign trail about specifics. The manifesto commitment to leave the Customs Union – a paragraph in an 88 page document that was overwhelmingly and famously about domestic policy – was not a serious exploration of practical reality. The entire section on leaving the European Union was a couple of pages. If we had won a majority then one, could have shrugged and said ‘so what’? – but we did not even manage to do this. Labour, even more paralysed by fear over the impact of Brexit on their voting coalition, were no better.

So the current state of affairs stems from a lack of honesty and a lack of a mandate. Next time, it must be different. We can only do this if candidates for Conservative Leader are rigorously interrogated by independent sources about the practical effects of their plans for the future relationship when they put themselves forward to party members. And similarly, in an election campaign, on the basis of a detailed manifesto, from which no can possibly argue that the Prime Minister lacks a mandate to proceed.

The Conservative Party might of course lose such an election if we confront this head-on. We might split. But acting bravely in the national interest while preventing these things is what marks out a leader from a pretender. There will also plainly need to be some attention focussed on core domestic priorities in the scenario I have outlined; it does not have to be purely black and white.

But what is certain is that the path ahead does not bode well if we pretend what lies ahead isn’t there; allowing the chaos of recent months to creep and compound itself once again as a repressed impulse. It will lead to similar results.