Was Boris Johnson drunk or “on something” when he wrote his 4,000-word magnum opus on Brexit for the Daily Telegraph, published this weekend? Probably not. He didn’t need to be. Rarely, if ever, has a senior cabinet minister, dealing with matters of the greatest urgency, written so vapidly, or in such rambling fashion, about the future direction of his country. What did he think he was doing? Those who know him assume he was making a thinly-disguised leadership bid, or at least throwing his hat back in the ring. But how much longer can he go on like this?

His essay is a masterclass in nonsense and non-sequiturs. We don’t need to dwell on the obvious. He wants us out of the European Union as soon as possible and has no time for the single market or the customs union. Fair enough. And the Britain he sees emerging from Brexit will be  a global champion of, well … everything. Let’s hope he’s right. It is in the detail of his argument that the Devil lurks.

First off, he wishes his readers to know that the 17.4 million voters who voted Leave in the referendum “weren’t fools, you know” – which must come as a relief to them. They weren’t stupid. “They weren’t as bad as some would have you believe. They were right, and even if you think they were wrong, I hope you agree that it is our duty, as democrats, to fulfil the mandate they gave us.”

Not stupid. Not “as bad as some would have you believe.” Talk about damning with faint praise. But even if they were wrong, the rest of us are, for some reason, duty bound to follow them up the garden path.

To do the wrong thing for the right reason. Boris’s inversion of Eliot could be the definition of populism.

A little further along, he observes of the UK: “Our infrastructure is too expensive – and takes far longer than France or other countries.” What does that even mean? Does he mean that French trains go faster, or does he mean it takes longer in the UK than in France to get things done? Either way, given that both countries are members of the European Union, whose fault is that? It sounds as if we’d be better off living in France.

But I digress. As indeed does he.

“Our vocational training is often superb – but still not inspirational, and we have yet to find a way of persuading middle-class kids that they might be just as well off getting a skill as a degree.” You think? So whose fault is that? Jean-Claude Juncker’s? What has our obsession with sending everyone to university got to do with the EU?

Moving on, Boris notes that the UK doesn’t conduct enough basic research in science. “I am afraid we still have too many schools that are content with second-best. The result of all these failings – over decades – is that we have low productivity: lower than France or Germany.” So, again, France and Germany are performing much better than we are? But how can that be? Have they secretly left the EU?

Soon, we pull up at the motherload of the Leave argument, as featured on the notorious battle bus. This is what we have been waiting for. “Once we have settled our accounts, we will take back control of roughly £350 million per week. It would be a fine thing, as many of us have pointed out, if a lot of that money went on the NHS, provided we use that cash injection to modernise and make the most of new technology.”

Quite so, except that the £350 million is not £350m. Even the Government recognises this. It is at most £200m (£3 a week per head) and is the amount due to Brussels from the country that during its 43 years of EU membership went from being the Sick Man of Europe to fifth-largest economy in the world. If all members states were net recipients of cash from the EU budget, the result would be a ponzi scheme. As it is, the £350m, as such, is nothing other than a myth.

From the absurd to the ridiculous, Boris next informs us that, post-Brexit, “at the stroke of a pen,” the Chancellor could cut the VAT on tampons. “This is often demanded by Parliament,” he tells us, “but – absurdly – it is legally impossible to deliver.” In fact, it was agreed at an EU summit in Brussels in March, 2016. And even if it wasn’t, is that a reason to leave the European Union? At least he didn’t mention straight bananas.

And so to the housing crisis. “It is often pointed out that the price of housing in certain parts of London may be pushed up by buyers from overseas. But there is no point in putting any kind of tax on foreign buyers, because the inhabitants of 27 other countries cannot legally be treated as foreign.”

Rubbish. The truth is that the foreigners in question are overwhelmingly from Russia, the Gulf states, Africa and South Asia. There is no reason such buyers cannot be dealt with under existing UK law. It just requires the Government to act. And if purely domestic legislation were to be passed, it would apply not only to UK investors, but to all EU buyers on an equal basis.

The Foreign Secretary next informs us that Britain is at the forefront of research on gene therapy, only to add that we are somehow hamstrung by red tape. So, we are ahead of the pack, yet held back by those pen-pushers in Brussels. It makes no sense.

Pausing only to point out that London has “gone a bit quiet” since he ceased being mayor (tell that to Sadiq Khan), Boris is keen to discover what happened to Minitel, “the state-owned and managed French equivalent of Google”. (Answer, it was 1970s technology that got left behind by the digital revolution.) What good, he wants to know, was all that talk in Brussels in the early Nineties about information networks? Did it produce a European champion? “Pas encore.”

This is the point at which he divulges that one of the four zones of the world in which large-scale high-tech investments are made is the UK, specifically “the triangle formed by London, Oxford and Cambridge”. He does not say in what way this welcome development was held up by Britain’s membership of the EU. He simply implies that with the dead hand of Europe lifted, our native genius will flourish like never before. Google should obviously watch out. The British are coming (again).

And when they do come, the lift-off, apparently, will be terrific. “My brother, Jo Johnson, is finalising the candidates for the location of a new UK space centre, and this Government is investing in the truly revolutionary Sabre project in Hampshire – a system that promises radically to reduce our journey times around this Earth.”

The British in orbit: a tantalising prospect. But no mention of the fact that going on for half of the top scientists and technicians behind the UK’s high-tech revolution are foreign, the majority of them citizens of the 27.

Lest – lest? – he sound jingoistic, Boris is quick to point out that Britain’s success “will not be a bad thing for our friends across the Channel.” On the contrary, “it will mean a bigger market in the UK for everything from Italian cars to German wine.” Brilliant. It used to be German cars and Italian wine, but what the Hell!

And so to the straight boasting. “We will be the largest military power in Europe, and with our growing defence budget we are now making an ever-more vivid commitment to the defence of Europe – like the new deployments in Estonia [800 soldiers] – and to our common European ideals and values.”

Never mind that our costly new aircraft carriers have no planes yet and that half our warships are out of commission, or that the Army is smaller than at any time since the rise of Napoleon. Britain, “as the second-greatest power on Earth after America,” is on the move, and the world had better bally well show us some respect.

Boris next gives us a glimpse into his days as a correspondent in Brussels for the Telegraph. “I used to look at the Brussels bumper stickers saying “Mon patrie, c’est Europe” and think it was a bit of a laugh, and that they would never engender a genuine Euro-patriotism, or compete with people’s natural feelings for their own country.”

But – mon Dieu! – he was wrong. “I have to say that I am now not so sure. I think I was complacent. I look at so many young people with the 12 stars lipsticked on their faces and I am troubled with the thought that people are beginning to have genuinely split allegiances.

“And when people say that they feel they have more in common with others in Europe than with people who voted Leave, I want to say: ‘But that is part of the reason why people voted Leave.’ ”

So! Millions of young people identified with Europe, and that is why we had to get out. What sort of an argument is that?

The Boris Memorandum, all 4,000 words of it, is scrappy, juvenile and incoherent. It was written – almost certainly in a single session – by an insecure minister desperate to prove that he has a vision for his country but is in fact all over the place, suffering, it seems, from early onset political dementia. He should resign, and if he doesn’t, he should be helped on his way. Our Foreign Secretary is a national embarrassment.