If a negotiation is like a card game, consider the Brexit one to come.  On the one side of the table will be our EU interlocutors, with their cards clamped close to their chest.  On the other will be Theresa May, attempting to do the same.  But standing close behind her will be the best part of 650 or so fellow MPs, demanding to know what’s in her hand, suggesting what should be, and shouting out any details they see.  No poker player could possibly win a game under these circumstances.  However tightly May might try to grip her cards with both hands, she would be playing, in such circumstances, with one of them tied behind her back.

This is now the most likely consequence of yesterday’s High Court judgement, a point whose significance has been missed by nearly everyone – amidst more cod constitutional cobblers about the role of Parliament, the privileges of the legislature, the tyranny of the executive, the place of judges, the Bill of Rights, Coke, Bagehot, Dicey, and all the rest of them than anyone has assembled since 1066 and All That, which in any event was satirical by intention rather than by accident, and a good deal more to the point.

Some Leave supporters have railed against the judges, claiming an establishment plot.  How much it must have cheered Nigel Farage, whose party is in danger of being put out of business by the referendum, to glimpse an opportunity to revive its fortunes!  Others leaned in the opposite direction, saying that the Prime Minister should have put the matter to a vote in Parliament in the first place – adding that MPs and peers will not dare to deny the verdict of the referendum, and will vote overwhelmingly to move Article 50 as soon as it is moved.  This is much closer to the mark.

But matters are not quite that straightforward.  As May herself pointed out yesterday evening, moving Article 50 will require not simply a vote but a Bill, and Bills are amendable, and must make their way through both houses of Parliament.  And make no mistake: while most MPs and peers simply want to influence the terms of Brexit, some of them want to stop it altogether.  From Nick Clegg through to Lord Kerr back again to Ken Clarke, there is a small group of parliamentarians who itch to raise two fingers to the biggest vote by the people in the post-war history of Britain.

That, after all, is what drove yesterday’s court case in the first place.  Gina Miller et al are not disinterested purists, seeking after constitutional truth.  They are Remain partisans fighting a no-holds-barred political battle.  They may well succeed in pushing Brexit itself back to beyond the next election, thus denying May the breathing space she wants before the latter takes place (though some elements of the settlement may well still be on the negotiating table then in any event).  It isn’t hard to see their game.  Quibble, niggle, question, nit-pick, qualify and procrastinate in the hope that the next election result somehow overturns last June’s verdict.

You may well counter that this is exactly what the legislature should do to the plans of the executive.  And, most certainly, Parliament is and (do we have to add?) should be sovereign.  There is no dispute – despite the attempts of some remainers to manufacture one – about that.  But it is simply beside the point.  So, too, is all the back and forth about whether the referendum verdict trumps Parliament’s place in the constitution.  (It does not.)  The question is not what MPs and peers are entitled to do, but what they would be wise to do.

Of course the Government should set out its aims to Parliament, and of course Parliamentarians should have their say on them.  Indeed, Ministers have set these out again and again.  Here they are in case you have somehow missed them, as set out by David Davis in the Commons itself only last month: “bringing back control of our laws to Parliament; bringing back control of decisions over immigration to the UK; maintaining the strong security co-operation we have with the EU; and establishing the freest possible market in goods and services with the EU and the rest of the world”.

And the Brexit Secretary should, as he and other Ministers have already been doing, answer questions in Parliament, respond to Opposition Day debates and hold their own in Government time, and be quizzed by Select Committees – of which two brand-new, Brexit-related ones have just been set up.  Oh, and just in case anyone had forgotten, the Government is already committed to bringing in a Brexit Bill – the “Great Repeal Bill” – which will give the legislature the opportunity to instruct the executive on the shape of Brexit to its heart’s content.

“The Parliamentary process will give a chance for the government, but also business, academic researchers and civil society to…work out what the priorities are when Article 50 is eventually invoked,” the UK in a Changing Europe said yesterday in the wake of the High Court’s decision.  But none of all this activity, both inside and outside Parliament, is taking place in splendid isolation.  The card game of that negotiation will soon begin.  And with all due respect to the distinguished professors of UK in a Changing Europe, they will not be playing Britain’s hand when it begins.  Nor will businesses, civil society – or, for that matter, the editors of ConservativeHome.

Nor will most MPs.  And there is a point at which advising May what cards to play becomes demanding she declare which ones are in her hand.  It is a distinction with a very big difference.  When Disraeli and Salisbury toddled off to the Congress of Berlin, they didn’t do so with a detailed instruction from the Commons about whether or not to try forming a Big Bulgaria.  They acted as Ministers and then reported to Parliament, which had the right to hold them to account.  Which, talking of the way our constitution works, was exactly as it should be.

When Stanley Baldwin confirmed Northern Ireland’s border with W.T.Cosgrove and James Craig, he didn’t do so with a specification from MPs in his pocket about on which side of it Crossmaglen should lie.  When Margaret Thatcher sat down with Gorbachev, she didn’t go with a prospectus from the Commons in that famous handbag.  But you get the point.  And the stakes in the coming Brexit negotiation are arguably even higher.  Prospects for exporters, opportunities for the City, the extent of security co-operation, family incomes, jobs – all will hang on the outcome.  The business May must transact is more than a showcase for legislative fun and games.

Parliamentary scrutiny, yes.  Instructing the Prime Minister exactly what cards to play, and blurting out her hand to our interlocutors, no.  May and pro-Leave campaigners should get ready to fight back if the Government loses its appeal.  Remain won in only three of England’s nine regions.  If vote “Vote Leave” had been a political party it “would probably have won 421 seats. A landslide representing 65 per cent of all seats (including Scotland) and 73 per cent of seats in England and Wales”, as Gary Bennett wrote on this site.

Most of the seats represented by diehard Remain MPs plumped unhestitangly for Brexit.  It is their Burkean right to act not as delegates but as representatives.  But they cannot complain if their constituents remind them of their views.  There is work for Change Britain and other pro-Leave campaigning groups here.  Just as there is for the Conservative whips, who should now rally Tory MPs to the Prime Minister’s support.  And if some make her task impossible, there can only be one outcome.  A general election.  I quite fancy her chances in one.  Don’t you?