"I don't normally respond to hostile points made about this column on our letters page", writes Booker
in this week's column. "But one example last week repeated a fundamental misconception so widely shared – not least by our politicians – that it merits an answer".
"Booker must stop saying", its author sternly enjoined, "that when we leave the EU we may not have access to its market. Everyone can sell or buy into Europe at any time... the market is open to all and always will be. Markets are not made by governments, they are made by buyers and sellers".
This view is so comprehensively wrong on every count, says Booker, that this week he is this week focusing on just one further important example, so far not mentioned, of what we are risking with Theresa May's decision that, on leaving the EU, we should leave not only its single market but also the wider European Economic Area (EEA), which would allow us to continue trading with the EU as we do now.
The whole point about the EU market is precisely that it is a market "made by government". It is like a fortress against the outside world, made up of a vast thicket of laws, regulations and procedures, all of which must be followed.
Picking up on the point I made on 6 February, Booker tells us that, if we choose to leave that fortress, we will find its drawbridge has been raised against us, making it very much more complicated to enter.
The particular example he gives is what will happen to all those thousands of British businesses that share in our £9 billion-a-year food exports to the EU. Once we leave, Britain becomes what it calls a "third country"; and all our animal-related products, deemed because of potential diseases to be "high risk", will then have to face the new set of rules that apply to any other "third country".
Apart from many other requirements, such as the need for Britain to be officially recognised as an "approved country", and for every food-related business to be subject to new EU inspections, the live animals, dairy products, eggs, fish and processed foods now carried smoothly to the Continent in trucks through Calais will have to be diverted to a "Border Inspection Post" (BIP), for a mass of new checks and inspections that could take days.
An additional problem is that the nearest BIP at Dunkirk is so small (despite a recent upgrade) that a much larger one will have to be built. To handle UK traffic, it would require facilities for hundreds of new officials and a vast waiting area for those queuing for inspection; all at a cost of tens of millions of euros, which the French would understandably expect Britain to pay.
For all those Welsh farmers who depend on selling lambs to the EU – where we currently export 385,000 sheep and 34,000 live cattle a year – or those cheesemakers and other businesses that export perishable goods requiring refrigeration.
This, says Booker, will pose immense practical problems; as will also be faced on the border between the north and south of Ireland, where some foods involved in processing can end up criss-crossing the border five times before they are ready to be sold.
Politicians may wave all this aside as just something else to be "sorted out in the negotiations". But the rules are the rules. They have no more idea of how tricky it may be to resolve this problem than they have so far shown any sign of recognising that it exists at all.
At the moment the movement of all this trade into the EU is, as Mrs May describes it, "frictionless". But if we leave the fortress on the terms she seems to be proposing, she has no idea how far this may involve not just the lifting of its drawbridge, but the raising of a mighty portcullis as well.
Of course, if she had the sense to keep us in the EEA, none of these problems would arise. But, by relying on her "Brexiteer" advisers, she may be facing rather stonier faces across that negotiating table than she has yet begun to imagine.
As we see, though, the Irish are waking up to the implications of a hard border, but not so commenters on the Booker columns.
In and amongst the ritual jibes that Booker has become a "remoaner", there is no evidence of even a scintilla of understanding of the position in which we will find ourselves, making the comments a no-go area for sentient beings.
This itself is not a unique phenomenon – the comments on the Telegraph are generally a vile place to be – but it does indicate how a self-selecting minority of "brexiteers" have simply stopped thinking (if they ever actually started).
Generally speaking, though, it is not even worth trying to engage – no amount of argument, or resort to evidence – will penetrate the bovine stupidity of this claque. The worry is, though, that so many of the sentiments expressed seem to be shared by the Government, and even endorsed by Mrs May.
In the end, though, reality will take its toll. From being a fully paid-up member of the European Union, the UK will in due course revert to the status of a "third country". If we are fortunate, and against all the odds, the Government will negotiate a tolerable exit settlement, but things are not going to be the same as before (and neither would we want them to be).
However, since Mrs May, in rejecting the Efta-EEA option, appears to have turned her face against the most effective means of managing our transition from EU member to independent state, the road is going to be far bumpier and more difficult than it needs to be.
All we can do, and will continue to do, is point out the pitfalls. This is not done out of any intent to suggest that we should not leave the EU – merely, it is common sense on a difficult road to mark out the hazards, better to enable us to deal with them.
For those, however, who regard roadsigns as a form of betrayal, theirs is the precipitous path over the cliff edge. The outrageous thing out it is that these idiots seem intent on taking us over with them.