Garvan Walshe is a former national and international security policy adviser to the Conservative party. He runs TRD Policy.

Politically-interested England Rugby fans faced an agonising choice on Saturday: watch the debate on the Letwin Amendment or England’s thrilling victory over the Wallabies. Sport made less comfortable viewing for the DUP, as Ireland’s nerve deserted them in an embarrassing 46-14 defeat to the All Blacks.

(As ConservativeHome readers will know, though Ireland has an all-island rugby team, rugby in Ulster draws its strength mainly from the Unionist community there.)

There is a phenomenon in rugby by which the closer a team gets to the try line, the more errors mount up – failure of nerve, the seemingly inexplicable habit of missing passes, knocking the ball on, committing technical infractions of rules “at the breakdown” so complex they would bewilder the most seasoned constitutional lawyer – a tendency known as ‘white line fever’.

As Brexit gets nearer, it’s a disease that seems to have established itself in the mind of the government.

An attempt to prorogue Parliament was penalised by the Nigel Owens of the Constitution, Lady Hale, and provoked the Government’s opponents to pass Benn-Burt Act to force it to seek an extension.

Under pressure from the EU, Johnson made a series of concessions, eliminating the backstop, but only by agreeing to the EU’s objectives. That Northern Irish companies would have to complete customs declarations just to sell (one cannot, surely, describe the activity as exporting) to the rest of the UK, shows why the DUP could not support this agreement.

Losing the DUP had perhaps become inevitable. No Deal, scarcely a credible option in any case, was made worse by the failure to take the steps needed to prepare for it (chiefly building the necessary infrastructure in Kent). This was not Johnson’s fault (the irresponsibility in this case was Philip Hammond’s, and perhaps his revenge for May’s threats to sack him during the 2017 election campaign), but it was nevertheless something he should have taken into account.

Given that the DUP were lost, the Government had two options open to it. Either find the votes elsewhere in Parliament, or seek an election in an attempt to clear the air.

A government that commands a majority, and therefore influence over the careers of members of its own party, can assemble support, even on an issue as divisive as this, by threats and patronage. A government whose majority is -63 (two thirds of which figure is attributable to its own purge) cannot. It needs to cajole, stroke egos, and, let it be said, persuade with rational argument.

MPs’ egos were hardly stroked by the sledging (forgive the mixing of sports here) from anonymous Number 10 sources. But trying to smash the Withdrawal Agreement (Implementation) Bill through on a ridiculous timetable was as unwise as Irish fly-half Jonathan Sexton’s failures to find touch through over-ambitious kicking last Saturday.

Those missed kicks cost Ireland the match. The parliamentary situation is now almost as dire. Though the vote on the Second Reading of the Bill passed comfortably, the Government would do well to suspect that the Bill was let through only to be surrounded and ambushed. It would emerge from committee stage, but mutilated by amendments calling for a customs union, or even another referendum.

The Government now has two options. The first, a sharp little “sniping” run, as the rugby commentators put it, would be to somehow engineer a very short conditional extension to give enough time for the WAIB to be debated. This carries two risks: not only that the Bill be amended to subvert instead of implement the deal, but also that it is ruled off-side as engineering such an extension would likely contravene the Benn-Burt Act.

Better to slow things down, “go through the phases,” accept the extension, and fight an election (which Corbyn has committed to accepting) on leaving with this deal. Obtaining the deal has improved the electoral arguments considerably. Tories can now rule out No Deal, which will limit defections to the Lib Dems. This Withdrawal Agreement gets the UK out of the EU and provides a basis to negotiate the future relationship. The Government’s position on that future relationship is not perhaps to my taste; indeed, if it had been, I would not have opposed Brexit. It is however very much within the range of outcomes canvassed by the Leave campaign, and a case can be made that the economic disruption it will cause to manufacturing industry is both worth it for political gains (in sovereignty, control over immigration policy, and so on), and beneficial because that type of manufacturing is not where Britain’s comparative advantage, as a service led economy, lies. Of course, if this is adopted, some calibration of electoral strategy is needed, with less emphasis on winning over manufacturing centres in the North and more concentration on an open and optimistic post-Brexit future for England and Wales.

I say England and Wales because a consequence of this deal will, later if not sooner, be Scottish independence, unless that can be forestalled by offering Scotland some arrangement similar to Northern Ireland’s. Indeed, in an election where the Conservatives fall just short of a majority (the try), an arrangement whereby this deal were put in place, but Scots allowed another independence referendum (the conversion), might well be the way to finally get Brexit done. Either Scotland votes to stay in, knowing the Brexit outcome that would entail, and dealing a decisive blow to the independence movement; or it votes to leave the UK, in which case a Conservative government in London could spend the rest of its term in office with a stable majority for the first time since 1987.