There has been a lot of talk in recent days – indeed, every day for the last two months – about the “arrogance” of the Remain camp. Apparently we are refusing to accept the Verdict of the People, solemnly given on June 23 and bounden upon HM Government as if it were the word of God.

The essence of the charge is that we, the Remainers, think we can ignore the largest-ever vote on a single issue by the British people since the beginning of time. The fact that the Remain vote was the second-largest such vote ever cast, and almost equally ginormous, is, er … ignored.

I blame David Cameron for this. Had the former Prime Minister, now more than ever yesterday’s man, written into the Referendum Bill a clause requiring that a vote to leave the EU should have to be carried by a two-thirds margin, or even by 55 per cent plus one, we would, in European terms, still be buggering on.

Such a requirement would have been perfectly reasonable. The people are a fickle bunch, who change their minds every other week. Most of them haven’t a clue when it comes to the economy or the reality of pooled sovereignty, which is hardly surprising given the complexity of the issues. You might as well ask them to vote on the existence or not of the Higgs Boson particle. All they know with reasonable certitude is that they don’t like sitting in their doctor’s surgery surrounded by people speaking Polish and Lithuanian.

Cameron couldn’t see this. He thought he’d get away with it. He thought his ragbag of petty reforms would be enough to tip the scales, not realising it would sink like a sackful of unwanted kittens tossed into the local canal.

But, hey, we are where we are. The die has been cast. The wheel is no longer in spin. To borrow a phrase, Brexit means Brexit. The three-legged tag-team (Johnson, Davis & Fox) charged with negotiating the terms of our departure is, we are assured, making its way towards the finish line with the kind of precision and common purpose normally associated with Olympic dressage. But, honestly, would you trust any of the three of them further than you could throw a sofa? (I say, steady on: Editor)

Time to get real. In the talks that will follow the triggering of Article 50, there should be two main objectives:

1. We should aim either to stay within the Single Market (not possible without overturning the anti-immigrant applecart), or, more plausibly, to achieve a settlement that combines a modest UK contribution towards the EU budget (say, 25% of what we pay today) with nominal tariffs on goods and services in return for passport rights for the City of London. Trade with the EU is simply too important, and too immediate, to be lumped in with the vagaries of global trade.

British companies doing business in Europe need to know which rules they have to obey, which standards they are obliged to meet and how much it is going to cost them. London-based banks and other financial institutions have to be free to operate across Europe as insiders, enjoying equal access and subject to the same rules and regulations. Without such freedom, many of the big names now trading in the City will move, over time, to Frankfurt, Paris, Luxembourg, Dublin and Milan, all of which are currently laying out their stalls. In leaving, they would take with them not only their billions in tax contributions but as many as 20,000 jobs.

Brexiteers like to imagine that London can become the Singapore of the West. But, irony aside (it was only when Britain left that Singapore became Asia’s entrepôt) London’s main selling point in the 21st century is that it is the prime financial centre of the EU, valued by New York, Zurich and Hong Kong precisely because it is their one-stop point of access into Europe. Take that access away and the City could implode.

2. A deal should be agreed that allows present-day immigrants from the EU, as well as those set to arrive between now and the end of next year, to continue to live and work in the UK in return for the right of existing expat Brits to live and work (or retire) in Europe. Such a deal, to include a basic level of reciprocal health-cover, would lay down a requirement that both groups pay their taxes in full and live as respectful citizens in their adopted countries. Workers and retirees planning to move beyond the starting date of the new regime would have to apply for work permits or right of residence, subject to the rules and procedures of the host nation. The UK on one side and (most obviously) France and Spain on the other would be free to make their own decisions on who to admit and who to reject, based on supply and demand.

Goodwill would be a vital element in this. No one with an ounce of sense would wish to see barriers erected that in effect cut off the British people from their European hinterland or caused European governments to view the UK as hostile territory.

Beyond these two absolutes, it would greatly assist the process if Britain, as Tim Montgomerie argued in Thursday’s Times, showed itself willing and able to work closely with the rest of Europe in the areas of security, immigration and defence. It is not enough to say that M15 can protect the UK from terrorists and Russian plots. How much evidence do we need to prove that cooperation in these crucial areas is superior to Chinese whispers? Theresa May, who understands this better than most, has to make it clear that Britain stands ready to lend its expertise, and what is left of our military might, to the entire Continent, to our mutual benefit.

Overall, what is most needed as we prepare to disengage from our former destiny, is a liberal, open-minded approach. Britain may have chosen to leave the EU; it has expressed no desire to leave Europe. Millions of us cross the Channel each year for all sorts of reasons, and we don’t want a return to the days of long queues at customs, punitive personal allowances, high roaming charges and increased fees at cash-machines. Even if we can’t have free access to the single market, we should still be free to participate as individuals in wider European society.

All of this has to be negotiated. And it will take time. As things stand, no one knows how much European legislation will have to be absorbed into UK law, but it is likely to be a great deal. Nor does anyone know the volume of EU regulations that will need to be incorporated or amended to ensure not only that trade continues uninterrupted but that productive cooperation at all levels – for example between universities and research institutes – ­ is not asphyxiated by mutually exclusive profusions of red tape. Anyone who remembers Yes Minister, one of whose writers, Antony Jay, died this week, will know that leaving the EU does not mean abandoning bureaucracy. For a start, there are said to be only around 200 Britons with real expertise in the nuts and bolts of global trade. We need hundreds, if not thousands, more, and they don’t grow on trees.

I’m not one of those who pretend that the people on June 23 were just clearing their throat. I think Labour’s Owen Smith is barking up the wrong tree if he thinks that Remainers can have a second bite at the referendum cherry – an image as troublesome in metaphor as it would be constitutionally. I wish this were not so. I wish, while ruefully acknowledging the extent of the various crises gripping Europe, that I could somehow erase the British verdict, delivered, by a wafer-thin majority after campaigns long on fear and short on facts. But I can’t, and the important thing now is to get on with the business in hand in a business-like manner.

Divorce is painful, even when it is the right thing to do. There is always a cost. Those who believe we can walk away from Europe with scarcely a backwards glance are fooling themselves even more than Smith is fooling … well, nobody at all. There is much at stake and what is important is that we present ourselves as grown-ups to our European partners – whose problems we have made immeasurably worse – and negotiate a grown-up settlement. It won’t be easy, but it will be worth it in the end.

You know it makes sense.