It was while I was on my way out of a reception, amid the imperial grandeur of the Foreign and Commonwealth Office, that I learned that our new prime minister had appointed Brexit’s most charismatic liar as her – and, I am afraid, our – foreign secretary.

What a farce. What an insult to us all, and to the world at large. Last week, Alexander “Boris” Johnson got what he deserved from the American press corps travelling with the US secretary of state, John Kerry. They had little time for such characteristically blustering nonsense as Johnson’s protestation: “There is a rich thesaurus of things that I have said that have, one way or the other, I don’t know how … been misconstrued.”

That was not the only surprise of the evening. When I got to Whitehall, whom should I bump into outside the Red Lion pub but my old friend David Davis. “Well, David,” I said, “I am sorry that your side won, but, as you know, I have always admired your stand on civil liberties.”

“Oh, I am not allowed to speak on that subject any more. They have just made me Mr Brexit.”

Wow! That was the first I had heard of his appointment. From the horse’s mouth! (By the way, I should emphasise that I did not get where I am today by revealing the contents of private conversations with ministers or officials, but this was a jovial exchange in the hearing of at least half a dozen members of the public.)

Well, now Davis and his fellow Brexiteers are in the hot seats. But it is already perfectly obvious that they had no plan and they are still struggling to dream one up. They are hopelessly confused about trade and the real meaning of trade negotiations. It is pointless criticising Cameron and his chancellor for not having prepared for Brexit. They quite rightly did not want Brexit. But it is truly amazing that the Brexit camp were happy to mislead sufficient members of an embarrassingly ill-informed British public into voting for something they had no idea how to handle. We seem to be in the absurd position where those of our leaders such as Theresa May, who were in the Remain camp, are saying “Brexit means Brexit” while the Brexit lot are trying to say, “Well, Brexit does not really mean Brexit. After all, we still want all the advantages of the club we have rejected.” And, of course, the shamelessly meretricious Nigel Farage continues to go to the European parliament to collect his dirty EU money.

This means Brexit, does it? But what does Brexit mean?

Apparently, it means keeping all the hard-won advantages of the single market – largely a British initiative in the mid-1980s – while fooling those people whose prime concern was immigration that “something will be done”.

If there are changes in the EU’s approach to the free movement of labour, they will not come about as a result of any desire to yield to the UK, but only if the migration crisis becomes even worse. Meanwhile, it can only be unsettling for the many immigrant workers on whom our economy depends that there is so much uncertainty, and talk of using them as “bargaining chips”.

During a recent visit to University College Hospital, I was told that 1,300 EU nationals were working there, and many fear what may happen next. In which context, it is good to see that London restaurant owners such as Richard Caring are promising to fight “tooth and nail” to preserve their staff’s rights to remain here, after what he describes as the “absurd” Brexit vote.

Many of the people who go on about immigrants are just plain prejudiced, but by now it is commonly accepted that successive governments have neglected to tackle the pressures on public services associated with immigration in certain areas, and there are legitimate concerns.

However, departing from the EU is not a solution. Being serious about governing on behalf of the entire nation and focusing on the concerns and problems of the forgotten towns of the north will be part of the solution – that is, if May actually means what she says. These are early days.

Meanwhile, the postmortems continue. In an article in the Financial Times, Peter Mandelson – a supposedly heavy hitter of the Remain campaign – sounded almost incandescent about David Cameron’s over-confident belief that, after a string of political successes, he could easily triumph in the referendum. I have heard similar charges about the former prime minister’s arrogant approach from one of his ministerial colleagues.

Possibly the most damning criticism of Cameron is contained in an open letter to him from Jeremy Kinsman, former Canadian ambassador to the EU, and high commissioner to the UK.

Referendums, he writes, “are the nuclear weapons of democracy. In parliamentary systems they are redundant. Seeking a simplistic binary yes/no answer to complex questions, they succumb to emotion and run amok. Their destructive aftermath lasts for generations.”

Despite the way in which so many people have meekly caved in to the supposed “will of the people”, I have not given up hope that something could emerge from the wreckage. Delaying the triggering of Article 50 until next year at the earliest may yet offer time for sense to prevail. We live in a parliamentary democracy, and it is estimated by those in a position to know that some three-quarters of the members of the House of Commons and Lords oppose this Brexit farce.

Let us hope they do everything in their power to ward off that destructive aftermath.