David Davis, the Brexit minister, is old and wise enough to know that the phrase “this time it will be different” normally presages disaster.
It’s precisely because history rhymes, especially when it comes to agreements between institutions, that his claim that our deal with the EU will be “like no other in history” does not exactly inspire confidence.
The more unusual and complex our aims, the greater the risk of failure.
Which is not to say that withdrawing from the EU was ever going to be simple or easy, given that our economies, laws and security arrangements are so intimately entwined.
But withdrawal would be less fraught if we weren’t intent on doing something sui generis, if we weren’t obsessed with engineering a bespoke new relationship with the EU.
However, Theresa May has explicitly chosen complexity and the unique as a matter of British policy, by stating as facts that the referendum on June 23 2016 were votes for us to “take back control of immigration and laws” – such that, in her view, we must have complete discretion over who comes to work here, and such that the European Court of Justice has no future influence over our laws or sway over our people.
Now for the avoidance of doubt, these are not empirically provable facts about what the British people want. They are interpretations designed to minimise the potential for civil war within her own divided Tory party.
And the important point is that in trying to reduce trouble close to home for her among her Conservative colleagues, she increased the potential for trouble in the talks themselves.
Without her two hang-ups about the European Court of Justice and free movement of labour, the UK could have significantly improved the climate for today’s start of talks by pointing to the arrangements for access to Europe’s single market enjoyed in different ways by Norway and Switzerland, and said we’d quite like some of that.
Obviously the structural and size differences between the UK on the one hand and Norway and Switzerland on the other mean we would end up with a differentiated trade and commercial agreement. We were never going to be able to wear exactly the same suit they put on.
But securing that differentiated agreement would be so much easier if we were re-purposing and re-fashioning off-the-shelf rather than insisting that there is no precedent for what we want. David Davis’s insistence on making history leaves our interlocutors from the rest of the EU anxious and confused about our ambitions.
Now it seems to me that the one person in government who appears conscious that it is not brilliant economics to re-invent the wheel is the Chancellor – who came on Peston on Sunday yesterday with two apparent aims.
The first was to prove that having been sent into exile during the General Election campaign by a Prime Minister who mistrusts him, he’s back and is more confident than he’s ever been (the confidence of chancellors is in direct correlation with the weakness of prime ministers).
The second was to stress that the top priority for the government as talks start should be to secure agreement from the rest of the EU that we can remain de facto members of Europe’s single market and customs union beyond the target date of March 2019 for the end of Brexit talks.
Because he knows that there is a huge danger that we won’t have negotiated our bespoke new trading arrangements by then.
And if we were to tumble out of the EU without any deal, our businesses would be mullered by the tariffs they would be forced to incur on trading with our biggest market, there would be chaos at ports and airports caused by the re-imposition of customs checks, and there would be a spike in the prices of very basic imported goods, and probable shortages too.
To ward off the more extreme Brexit shock to the UK economy, a process of transition to our unknowable future relationship with the EU is everything (as I have been banging on about for a year).
Common sense, you might think.
But the important point is that Hammond came on Peston on Sunday not to describe the negotiating approach actually being taken by May and Davis, but to lobby them.
He was saying that we ought to put “transition arrangements” at the top of the negotiating agenda, knowing full well that May and Davis are aiming for no such thing.
Why are they refusing to do this?
Well they are aware that for Brexit purists like the International Trade Secretary Liam Fox and his many Tory backbench allies, “transition” – in which we would be probably be a temporary member of the European Economic Area, enjoying full access to the European Single Market, but not being able to prevent European nationals from coming to work here at will – is a Trojan Horse.
They fear that once we are out of the EU and trading comfortably with the rest of the EU under interim Norway-style arrangements, the urgency will come out of negotiations for full rupture: the temporary stop will become permanent, we’ll be in what they think of as purgatory for an eternity.
Now the thing is, Brexit purists like Fox are almost certainly right, that a transition deal could very easily morph into forever.
But in viewing transition as the ultimate act of betrayal, the Brexit ultras may – in a House of Commons reconfigured by May’s election – turn out to be the exception rather than the rule.
So whether by accident or design, we may well Brexit to single-market and customs-union membership as a result of muddling through.
Which, and hello David Davis, would be quite like every other British deal in history.