Neither Theresa May nor Jeremy Corbyn have the solution to Brexit

The colour of the cherries may differ – Mr Corbyn wants strong workers’ rights; Ms May, presumably, lower corporate taxes – but the idea of cherry-picking policies is the same, and just as unacceptable to the EU27

Even taking a charitable, flexible, positive view of Mr Corbyn's Brexit plan, it would be unlikely to survive its first skirmishes with reality (Rex)

As a dedicated Arsenal fan, albeit one who must be disappointed at his team’s loss to Manchester City in the final of the Carabao Cup, Jeremy Corbyn should understand how pro-Europeans will see his keynote speech as a “game of two halves”. In one address, Mr Corbyn managed to both sound and feel more solidly sensible about Europe than the Government, in committing to the EU customs union; but he also confounded those, especially in his own party, who hoped that he would couple that with a pledge to stay in the EU single market, arguably a more valuable prize.

The Labour leader did his best to solve a notoriously knotty conundrum: how to be a member of a customs union, which is defined as a club of countries with a common trade policy towards the rest of the world, but also to retain the freedom to negotiate free trade deals with other countries in the British interest. In Mr Corbyn’s words: “We are also clear that the option of a new UK customs union with the EU would need to ensure the UK has a say in future trade deals ... A new customs arrangement would depend on Britain being able to negotiate agreement of new trade deals in our national interest.”

The answer, apparently, is to have the British to tag along with the EU trade commissioners in such talks, in a sort of vaguely defined co-determination role – “a say”. It appears – the detail is lacking – to be more than mere consultation, which is a matter of diplomatic courtesy, but short of the kind of full power of veto that EU members (and their constituent regional and provincial parliaments) currently enjoy. In a technical sense, the first EU trade deal that would be settled after Brexit would be one with the UK, which, under a literal reading of Mr Corbyn’s proposal, would mean the UK negotiating with itself. Quite a looking-glass world, then.

Even taking a charitable, flexible, positive view of Mr Corbyn’s idea, it would be unlikely to survive its first skirmishes with reality. There may well be many areas where the UK’s trading interests coincide perfectly with some of the EU27. Not necessarily, though.

Inevitably, there will be times where they diverge. The whole point of Brexit, after all, was to maximise the opportunities offered to, for example, source food more cheaply on world markets without having to worry about the proverbial French and German small farmers protected by the common agricultural policy. So how would a trade deal with, say, the US on cereal imports work both for the French and the EU on one side, but also the British on the other? There could, as in all things, be compromise. Yet that would complicate what would already be complex bilateral talks between the EU and the US, say, by turning them into a three-cornered affair. That, if anything else, would be a prescription for delay, if not endless wrangling.

The second problem with the Labour policy is that the European Commission would simply find it too irksome to have British government ministers turning up for talks when ministers from, say, the Netherlands, or Sweden or Italy aren’t invited to offer direct input and protect national interests. Of course, the EU might, on effect, “sell” a seat at the trade talks table to the UK, but, again, that was hardly what anyone had in mind at the time of the referendum. “A say” on EU trade policy and the customs union, even so, is just about feasible.

Yet while he has warmed to the customs union, on the single market Mr Corbyn has set his face against it more harshly than ever by making impossible demands. In effect, though he did not put it so crudely, if Mr Corbyn wishes to save the Port Talbot steelworks, he does not wish to be told by some Eurocrat in Brussels that he cannot do so because of EU single market rules on state aid, or whatever. In Mr Corbyn’s formulation: “Labour would negotiate a new and strong relationship with the single market that includes full tariff-free access and a floor under existing rights, standards and protections ... So we would also seek to negotiate protections, clarifications or exemptions where necessary in relation to privatisation and public service competition directives state aid and procurement rules and the posted workers directive.”

That does sound like the kind of “cherry-picking” that the EU finds so unacceptable – and identical in principle to the Conservative policy hammered out at Chequers. The colour of the cherries may differ – Mr Corbyn wants strong workers’ rights, Ms May, presumably, lower corporate taxes – but the idea is the same, and just as unacceptable to the EU27.

It all comes on the day that David Lidington, the Government’s Brexit gopher, made it clear that Whitehall and Westminster would have the final say on which powers currently exercised by Brussels will be devolved to Edinburgh, Cardiff and Belfast – under the cover of a commitment to the UK’s “common market” and international obligations. It was a pretty threadbare effort to disguise the latest power-grab by Conservatives who, in truth, never cared much for the devolved settlements, including, in the more Orangey corners of the party, the Good Friday Agreement. Nicola Sturgeon should throw it out.

Next week, after the Prime Minister makes her last-ditch attempt to appease Tory rebels on the Trade Bill, the Government will be faced with the first of many defeats on its Brexit legislation. Grave as it would be, it would not be fatal; as in the 1990s and the passage of the Maastricht Treaty, the Prime Minister can simply call a vote of confidence in Her Majesty’s Government, which she’d almost certainly win, and carry on with some other formulation on Brexit, stumbling along until the next crisis.

It is no way to run a country, nor to run Brexit; but it is not immediately clear how things would be much less chaotic under Mr Corbyn. Like Arsenal Football Club, it looks like Britain just can’t win at the moment.