It is an astonishing anthropological experience to stand in a row of people waiting to greet a member of the Royal Family. If you ever get the chance, you should look carefully at your neighbours.

You will spot someone that you know for a fact is a rabid leftie – a card-carrying socialist and egalitarian. There are so many lefties these days that it is, I am afraid, a statistical inevitability.

As the royal personage draws ever nearer, shaking hands as they go, I suggest that you scrutinise your Left-wing acquaintance carefully – because it doesn’t matter what they generally say about the royals or how critical they may be.

They may deplore their lavatorial sense of humour; they may sneer at their O-levels in home economics; they may wax indignant at their lust for bloodsports and their peculiar and so far unsubstantiated requirement that a special equerry should always be on hand, wherever they go, to warm the seat of their loo.

You may be standing next to someone who is, in principle, an out-and-out republican who would happily sell off Buckingham Palace for social housing and turn Sandringham into allotments for asylum seekers.

But by heaven, I tell you this, with the confidence of someone who has seen it happen many times: when the moment finally comes for the royal gaze to light upon that Left-wing republican, when they are bathed in the dazzle of the royal dentition, you will notice a sudden change in their demeanour.

They hold their breath. They stiffen their spines. They perform the bow or curtsy that they have practised all morning. And after they have held a brief, stammering but wholly cordial conversation with that member of the royal tribe they will remember it for the rest of their lives, and repeat it with forgivable embellishment until their dying day.

That is because there is no institution in the world that has the magnetic pull of the British Royal Family.

Harry and Meghan visiting Chichester in 2018. When the moment finally comes for the royal gaze to light upon that Left-wing republican, when they are bathed in the dazzle of the royal dentition, you will notice a sudden change in their demeanour, writes Boris Johnson

There is something about it that speaks to the depths of the British soul – the idea of a monarchy that genetically personifies the very history of the country, and that somehow represents the best of the national spirit in a way that transcends the Left and Right of politics.

Millions of people in this country have by now had that royal experience – of first-hand eyeball-to-eyeball contact with a real, live, dinkum member of The Firm; and yet the sad truth is that there are many millions more who have not, and who long to do so, and who perhaps never will, for the simple reason that there just aren’t enough of them to go around.

All of which, of course, makes it fundamentally excellent news that Harry and Meghan have decided to call time on their sojourn in America – where it seems to me that, apart from selling an incredible quantity of jam (or not), they were slightly under-appreciated – and to come back to this country.

It is time for the courtiers to get a grip on events, to make the most of it, and to go back to the secret strategy that they came up with a few years ago. It was called ‘The Big Six’, a reference to the big beasts of the African savannah, the ones the tourist absolutely must see (let’s call them lion, elephant, rhino, giraffe, leopard, buffalo).

I remember I was standing in some giant Commonwealth reception at Buckingham Palace, right next to the author of the strategy when I first heard about it. I will protect his name, but in the old days he would have been called something like Sir Alan Fitztightly.

‘Look,’ said Fitztightly suddenly, in an Attenborough whisper. ‘The Big Six!’

And there they were – all together – coming through the crowd in a kind of phalanx: the Queen and the Duke of Edinburgh, followed by the then Prince and Princess of Wales (aka Charles and Camilla), followed by the Duke and Duchess of Cambridge (William and Kate).

They were causing a sensation as they went – not surprisingly. How would you feel if you saw – under the same baobab tree – a collection of six large mammals made up of lion, elephant, rhino, giraffe, leopard, buffalo?

Harry and Meghan greet members of the public in Dusseldorf, Germany, in 2022

You’d think it was mind-blowing, astonishing, because each of those alone is worth travelling to Africa to see. That was the essence of the Big Six strategy – to focus on those members of the family that the public really wanted to see more than anyone else.

That was not to deprecate the work of the other royals, notably Princess Anne. They were and are loved and appreciated. They did great stuff (I think this was before Prince Andrew blew up). But the Big Six strategy was about maximising and co-ordinating the impact of the core team.

Well, my friends, you can see where this argument is going. Since that strategy was devised, we have sadly lost both the Queen and the Duke of Edinburgh. There are fewer big beasts around the waterhole, and you could argue that the Big Six has in fact been reduced to four.

So it is of great interest that two of the most charismatic megafaunas are coming back to the Pride Lands because, whatever you may say about Harry and Meghan, they are certainly capable of making up the numbers. Look at the yards of coverage that is being devoted to their return!

As beasts go, they are the kind that will definitely cause a ring of Land Rovers to form around them with whirring telephotos; and that matters.

Think how this country works. Every day there are great campaigns being launched, or important public buildings being opened – projects on which people have worked hard, and where the presence of a senior member of the Royal Family would give those people a sense that their efforts are appreciated.

I know that Harry and Meghan could do it again. I have seen them in action. I am also aware that there is a tide of feeling against them, for all sorts of historic reasons. It is time for the Palace to go decisively against that tide and bring them back into the fold.

This is no moment for half measures. They can’t be semi-detached members of the Royal Family, and they certainly can’t set up some rival operation – an alternative court – that isn’t properly co-ordinated with the others.

They have a huge amount to offer. Think of the innocent pleasure they could bring to people around the country, simply by coming to thank them for what they have done for their community – and of course bringing the cameras with them.

Whatever hard words have been exchanged in the past – and like most readers, I have no idea of the details – this is the time for forgiveness. The whole lot of them need to let bygones be bygones, and bring them back in, for the good of the family, and the country as a whole.

Harry needs to get over whatever insults he perceives that he and his wife have endured and recognise that the work of The Firm is important, and that very few can do it. He should get stuck in.

As for his long-suffering father, it’s time to remember the parable of the Prodigal Son. Bring back the Big Six.