The Brexit deal agreed with the EU is a spectacular vindication of the Prime Minister’s approach: to go back to Brussels with the genuine prospect that Britain would leave with no deal on 31 October. The EU started off by saying it would never reopen the withdrawal agreement, but with a no-deal Brexit back in prospect, compromise — and thus a deal — has been possible. And yes, parliament has said it would force the Prime Minister to ask for an extension of EU membership; but No. 10 said it would find a way to not do so. It seems that this was enough to focus minds in Brussels.

Boris Johnson's deal is the opposite to that struck by Theresa May in that the more you look at it, the better it seems. Legally, we would leave the European Union at the end of this month. There follows a transition period: 14 months, rather than 21 months (ie, until the end of next year). Thereafter, the UK would have control over its borders, its waters, its farms and more. You can search in vain in the pages of the agreement for hidden nasties. There had been talk that France wanted access to British fish: there is no such concession. There are others, but not new ones. We continue to pay quite a lot of money, but the sum goes down quickly and we should save at least £70 billion over the next decade. Money that could be put to better use redressing the effects of a globalisation that has made London too powerful relative to the rest of the country.

The biggest concession, on our part, is that Northern Ireland can stay in an all-Ireland economy and would follow EU regulations on agriculture and industrial goods. But it also stays part of the UK Customs Union, meaning a two-border system with the UK/Northern Ireland regulatory border fairly lightly patrolled. Crucially, it can opt out of the all-Ireland system by means a simple majority vote in Stormont. So the backstop has gone: the Prime Minister has executed the "backstop-ectomy" that he promised. Democratic control stays in the UK, albeit under our devolved system. There is no unionist veto on the Stormont vote, to the dismay of the DUP.

But to agree to Belfast's control took a big concession from Leo Varadkar, the Taoiseach, who deserves credit in moving so quickly in the end. Brexiteers ought to acknowledge his role in this deal: it was made possible by genuine and significant compromise, from all sides. If the deal passes, there is an opportunity to move immediately to repairing relationships that have been strained by the Brexit talks. As Theresa May said, when the deal is agree Britain can start to position itself as the EU's biggest single ally, as Ireland's most influential friend.

The question this weekend is whether Westminster can now bring itself to compromise. Yes, there is plenty to complain about in the deal. It guarantees money, without any guarantees about the free trade deal. Labour MPs will worry about Britain being independent from EU regulations (the so-called 'level playing field') and perhaps use this to claim that massive lowering of standards will follow. This is nonsense, of course: Britain's future lies in ever-higher standards, high pay, higher skills and higher environmental protection: the agenda that Boris Johnson is out to pursue. But those who wish to pretend otherwise can look to his Brexit deal as a slasher's manifesto and find reasons to oppose it.

If the EU says it will not grant an extension, this will force MPs to choose: its deal, or the supposed no-deal chaos that opposition parties say they would oppose at all costs. It is now relatively easy for the EU to call their bluff. But if it does not do so, it will be a very close vote for the government - especially given that is 40 seats short of a majority.

It has become a commonplace to say that history will not treat someone or other kindly, but in Johnson’s case history could scarcely be any less sympathetic than many of his critics already have been. He has been dismissed as a fraud and a joke; and even his success in Brussels will be dressed up as something forced upon him by rebels.

Yes, he has made his fair share of mistakes. The prorogation of parliament backfired badly, and No. 10 did not imagine that Labour would refuse his call for a general election. But a more elegant solution was never available. He always had an easy riposte to his critics: what would they have him do? What course of action is more likely to settle this amicably? He could hardly resign and invite Jeremy Corbyn to lead a caretaker government — passing No. 10 to a man he claims is a danger to national security and supremely unfit for the office. If the House of Commons votes for a second referendum, that would likely lead to another Brexit victory and take us back to where we are now. To push through Theresa May’s deal for a fourth time would have been impossible with the MPs ranged against it. But to go for a modified version of that deal — as he ended up doing — was the most sensible compromise. Perhaps the only sensible compromise.

Even if it works — and until MPs back the deal, it remains an agonisingly big ‘if’ — an electoral benefit is not guaranteed. As Churchill found to his cost in 1945, the British do not tend to view elections as a chance to reward a government for past achievements — they will be looking ahead to see how a Johnson government might use a Commons majority.

We gained an insight into this through this week’s Queen’s Speech: it’s a pitch for the Labour Leave constituencies, with emphasis placed on health spending, school spending and controlling crime. We can expect him to take the George Osborne approach to tax cuts: in favour of them in theory, but never quite finding the right moment to implement them. With an election approaching, the Tories will promise more spending — and more debt to pay for it. As the coming budget will likely attest, austerity is over.

But what the electorate deserve to know above all else is: how is Boris Johnson going to make use of the trade and legislative freedoms for which he campaigned in the EU referendum? Without a coherent vision for this, Brexit will have been a waste of time. The Conservatives should not be shy. They should unashamedly seek to break the protectionist shackles which have held back the EU when trading with the rest of the world. Theresa May’s government was marked by a failure to explain what Brexit is for. Johnson rightly mocked her for it. But we could be hearing a lot more about his idea.

The coming general election will provide a greater contrast between the social and economic policies of the two main parties than has been seen since 1983. It will decide what sort of country post-Brexit Britain is to become: interventionist, large government, with a return to union power; or economically liberal, championing the rights of people and communities to make their own decisions. If the Conservatives become the Brexit party with nothing much to say beyond Brexit, then they are doomed.

When Boris Johnson declared that he would leave the EU by 31 October, it was seen as an impossibly ambitious goal. Now, it looks likely. All he has to do now is win Saturday's vote, win a parliamentary majority, keep the union together, stave off recession and agree a second Brexit deal when this one expires at the end of next year. The Prime Minister has always thought of himself as being blessed with good luck. This week's events will vindicate his suspicion. But he'll need plenty more luck before his high-wire act is over.