The argument over leaving the European Union is Britain’s least civil and most seismic disagreement, at least since the Irish question, a century or so back, that shaved off part of the country and irrevocably split the Liberal Party. Yes, it is that serious.  

Allow me, please, to make a declaration at the outset: that I want what’s best for Britain – not because of birth; my citizenship was renounced some 30 years ago – but because it’s in the best interests of the wider world that Britain be strong; and Britain can’t be its full-strength without also being free – free to set its own course and to chart its own future.

Let’s start with a little thought experiment: I suppose it’s not entirely beyond anyone’s comprehension that Australia might form a union with New Zealand, given that our constitution’s founders envisaged that our trans-Tasman siblings might once have joined our commonwealth; or even that we might somehow have a union of sorts with Papua New Guinea, that was once our colony.

But could anyone imagine, even in a wild fantasy, a south east Asian parliament with a supra-national government, based (say) in Singapore, attempting to make rules for countries as diverse as Australia, Indonesia, Malaysia, Vietnam and Thailand merely because we share a neighbourhood and the imagined alternative is war between us?

Given Europe’s blood-stained history, it’s easy to see the necessity of a close alliance between one-time foes, so that the generals of each country see each other as brothers-in-arms rather than as military rivals. Given the glories of Christendom, it’s easy to grasp nostalgia for a Europe with a common faith and a common culture, where the ruling elites feel as at-home with each other as once did a series of inter-related royal families.

But this idea of 28 quasi-independent countries, large and small, relatively rich and relatively poor, all with different languages, different histories, different ancient attachments, and different ancient antagonisms, all needing to act-in-unison, all heeding the same faceless Brussels bureaucrats and worshipping at the altar of climate change and uncontrolled borders – well, if this nostrum were put forward in an Australian pub the response would be to “tell ‘em they’re dreaming”.

And that would be the polite version, because this is not a formula for leadership but for paralysis.

As a free trade zone to promote mutual prosperity between relatively well-off neighbours, the European Economic Community as-it-then-was made much sense. That’s what Britain belatedly voted to join back in 1975.

It’s just that the evolution-by-stealth of this free trade zone, even then showing signs of “fortress Europe” with its wine lakes and butter mountains – without its inhabitants ever really being asked, or being ignored and by-passed if they ever had the temerity to say “stop” – had always been planned by those at-the-heart-of-Europe, in order to create a new entity commanding more loyalty than its member states.

And yes, the conservative instinct – that I completely understand and share – is not to change, without good reason, because change is often far more trouble than it’s worth. But when change must happen – because the people want it, because they want a polity that’s fully accountable to them – it’s not reform so much as restoration that’s called for: in this case, restoration of the free trade with the major countries of Europe that Britain thought it had signed up for back in 1972. 

Whenever the citizens of the different countries of Europe have been asked what they thought of “ever-closer union” their first response has always been to reject it. And oblivious to the ever-widening democratic deficit, the high priests of Europe have always found ways to subvert every outbreak of independence or of national feeling, through legal back channels or through bullying the local establishment into second votes, until the poor, old benighted majority of voters could be brought to see how misguided they’d been.

That’s what’s happening in Britain right now. The people voted to leave but the establishment wants to stay. It’s a revolt of the minority against the majority; of the elites against the voters; of the parliament against the people; of those who think “big brother knows best” against those who truly-think that “Jack’s as good as his master”.

I have heard it myself, again and again from the lips of good and decent people who would not normally scorn the articles of democratic faith: that some voters count more than others; and that you just can’t trust ordinary people to know what’s in their own best interests, especially when “their view doesn’t coincide with mine”.

Would the British people have voted to stay in the EU had they known how Brussels officialdom would work against them? Or how much Britain’s remain-voting top civil servants, professors and public company directors patronised them? Hardly!

Now that voters know that Brexit might – might – mean hold-ups at airports and wharves, while the EU works out what it wants to do; and fewer tourists, job losses and an investment drought until the uncertainty subsides, surely, surely – say the re-moaners – people would not have voted for it?

But hang on, that’s exactly what Project Fear predicted the first time round and vote-for-it is exactly what they did! No, the second vote movement is not a fight for democracy – it’s just a hypocritical bid to overturn the first vote by the losers who didn’t like its result.

Theresa May was right, at-the-outset, when she insisted that Brexit meant Brexit. What’s happening now is a determined campaign to stop Brexit happening at all; or to ensure that it’s a Brexit that doesn’t change anything, under the May deal, because for years to come, possibly forever, Britain is locked into the European single market but with no capacity to change the rules and no capacity to do any trade deals for itself.

The remainers, some of them at least, are prepared to concede that Britain will leave the political union but all of them still insist that it must stay in the economic one, because, deep down, they fear that Britain can’t cope on its own.

Yet this is the country that has seen off the Spanish Armada, the French Emperor, and the German Kaiser. Against Louis the fourteenth, against Napoleon, against Wilhelm the second, and then against Hitler, this country didn’t need Europe. It saved Europe, helped – as it always should be – by its friends and family, the Commonwealth across the sea.

This is the home of the mother of parliaments, of the industrial revolution, and of the world’s common language. That’s right; the modern world has been made in English; so no country on earth should be more capable than Britain of standing on its own two feet. That, surely, is what’s crying out now for remembrance, amidst all the decline-ism and defeatism, because if Brexit fails, Britain fails.

Deciding to leave the EU, but failing to carry it through, wouldn’t just be a normal failure, like failing to build the HS2 or to extend Heathrow. It would be defeat on an epic scale, hardly matched since the Norman invasion, a national humiliation to echo down the ages, shattering to all who have ever looked to this country for inspiration.

Not for nothing is it the British flag, that’s again seen on the streets of Hong Kong, 22 years after its people last-truly-knew freedom-under-the-law. If they thought that Britain would be lost in Europe, as they fear being lost in China, they’d hardly be carrying your flag. For them, it’s a symbol of freedom; and for you, surely, a source of pride in all-you-have-done and all-you-yet-can-do.

So let me reassure anyone in Britain, anxious about the prospect of a no-deal Brexit, that Australia does one hundred billion dollars’ worth of trade with the EU every single year, on the basis of no deal. Sure, we have some trade facilitation arrangements. These arise from the mutual self-interest that exists between any two entities that wish to do business with each other regardless of whether they are in some form of political union.

Come to think of it, Britain – yes Britain – already does 55 per cent of its trade with countries outside the EU on the basis of no deal. Indeed, it’s not Britain’s trade with the EU that’s growing but the trade it does with the rest of the world on a no-deal basis; trade with people who want to buy British goods and British services because they’re worth buying, not because they’re in a political union.

And I know something about trade deals because my government did them, trade deals covering almost 50 per cent of our exports – with Japan, with Korea, and with China. You can do them. But you have to know what you want; you have to be in charge of your own country; and your negotiating partners have to know – and this is the exact phrase – that “no deal is better than a bad deal”.

A full economic partnership between Britain and Australia – restoring the almost completely unrestricted commerce that we enjoyed for 150 years, and allowing Britons and Australians, once again, properly to experience each other’s wonderful countries and lives – would be about the best 2019 Christmas present our two countries could have.

Frankly, had our negotiators not been so timidly respectful of the EU’s rules, it could have been ready to sign and to commence from the 31st of October so that Britain would not be going into the world alone. There should be no easier deal to do than one between Britain and Australia – and with a new Prime Minister in-charge and with a new minister pushing hard, it certainly should be signed, sealed and delivered this year. 

None of this is all-that-complicated and it need not even be all-that-hard. Yet that, it seems to me, is what officialdom’s reluctance has made everything to do with Brexit. You’ve been so pre-occupied with what Europe might expect that you’ve neglected to plan for what you must do.

For almost 50 years, goods have been freely traded between Britain and the countries of the EU without tariff or quota or hold ups at the border. Offer to keep that.

For almost 50 years, something that could be sold in France (say) could be sold in Britain; and, more-or-less, someone who was qualified to work in France could work in Britain – and vice versa. There’s been full mutual recognition of standards and credentials. Offer to keep that.

Millions of people have come here from the continent to live and work. They’re good people. Let them stay for as long as they like and become citizens if they wish, and ask the same for Britons in Europe.

And as for the future, if people from Europe (or elsewhere) can come here to contribute, for work not welfare, and maybe their bosses can pay a foreign workers tax too, in order to ensure that no one’s wages are being undercut; within numerical limits, those people should have the same big-hearted welcome to Britain as they’ve long had. And Britain should seek the same for its citizens in Europe. 

With goodwill on Europe’s part, this could be agreed on the spot because it’s essentially maintaining what’s always been for the past 50 years. It would be what’s best for Europe and what’s best for Britain: indeed, better for them than for you, because Britain is a better market for Europe than the other way round; and Britain is a better economic opportunity for Europeans than the other way round.

And if the Europeans, to punish Britain, want to cut off their nose to spite their face, Britain could do it anyway, unilaterally. That way, if there was a hard border anywhere, including in Ireland, it wouldn’t be Britain’s doing, it would be Europe’s. It wouldn’t be Britain that was shutting out Europe, but Europe that would be shutting out Britain; and, in the long run, Europe has more to lose.

The Europeans know that. That’s why they’re so assiduously trying to exploit the fear of no-deal to bluff Britain into becoming an economic colony, stuck in the customs union but with no say whatsoever over making the rules – and that’s why Britain has to be ready to walk away with no deal to have any hope of getting a good one.

As far as Britain is concerned, Brexit need change nothing unless Britain decides it should. Post-Brexit, all existing EU rules would apply in Britain, until Britain decides otherwise. But no future EU rules would apply in Britain, unless Britain decided they should. No future EU tribunal decisions would apply in Britain. And no further payments would be made by Britain to the EU – not 39 billion pounds, not even 9 billion pounds – other than for specific common projects that Britain chooses to participate in.

Like parties to a bad marriage, Britain and the EU should make a clean break; and once done with it, will probably surprise themselves at how much better they can then get on.  

Still, the next few weeks will be full of political fury, as remainers plot to sabotage Brexit, or to turn it into a self-vindicating disaster. They will fail though, because in the end, there won’t be enough of them to usurp a democratic vote, to sacrifice their country for short-term political gain, and to put Europe before Britain.

As the scripture says, “he who put his hand to the plough and then turns back is not worthy of the Kingdom”.

Finally let me offer this reassurance: that if there’s one thing that writing a fine book on Churchill would have done for Britain’s new prime minister, it’s readying him for this challenge and to call it for Britain. This is his moment of destiny – as much as this country’s – and I’m sure that he feels that his whole life has been “but a preparation for this hour and for this trial”

And I know that with 27 EU countries now lined up against you, because they don’t want to lose a friend-at-court, or because they fear being upstaged by a Britain where people can so-much-more-easily get things done, you must often feel alone and full of doubt. How could you not?

But know this: there are some 160 other countries out there, too polite to take sides, but ready to welcome you back: back into a wider world; back into a bigger family; nearly all of them willing you to succeed; and just wanting you to get this done.