When Prince William visited the Dubai World Expo in 2020, I had the honour of meeting him in private before he went to greet the crowds outside.

As we spoke in the pavilion, we could hear the wall of cheers from British well-wishers punctuated with spontaneous renditions of Jerusalem.

‘Just so you are aware, you have large number of supporters outside,’ I said to him. ‘They are here for you.’

At which, for all his long experience, the prince blushed. He genuinely seemed abashed and, in that moment, I glimpsed real humility, an authentic, modern-day ordinariness.

William seemed to struggle with the fact that people really had gathered in Dubai, not merely for the Expo, but to greet him and support what he represents.

That was when I realised that the heir to the throne has inherited some of his father’s finest qualities. The apple never falls far from the tree.

I’m not going to lie, I am a huge monarchist. I’m fascinated by our heritage and our history.

The biggest honour of my life – bearing in mind that I lived on a council estate until my early twenties and was once a child-poverty statistic – was to be appointed a member of the Privy Council, the historic group that advises the monarch of the day.

I have no shame in saying I was reduced to tears when, voluntarily, I stood down from my role as Culture Secretary. It was partly because I was leaving the most amazing department and the most wonderful staff.

I was also sad because I knew it was unlikely that I would ever again meet the King, a man I’d had the honour of spending a little time with.

Charles embodies a kindness and humility. A sense of duty and work ethic ooze from his very pores. They are qualities you cannot help but be impressed by.

I will always be the biggest defender of our royal family. So it is with great sorrow that even I have to admit the true extent of the damage caused by the man formerly known as Prince Andrew.

His disgrace marks the beginning of the end for the monarchy as we know it.

Much of what King Charles and his mother, the late Queen Elizabeth, had been working towards has, thanks to Andrew, been destroyed.

Until recent events, I thought that the royals had pulled it off. That they’d kept the show on the road despite the antics of Prince Harry and his plastic princess, Meghan.

Following the King’s decisive action in banishing Andrew to Norfolk, there will be plenty who believe that the furore surrounding his friendship with paedophile Jeffrey Epstein will fade and that, in due course, life for the royal family will return to normal.

I am very certain that it won’t. There will be more bombshells, more shock waves to come.

Who would bet against Sarah Ferguson writing a memoir of her own one day, her quill pen sharpened and dipped in bitterness? Her motive will be to earn money; her excuse – to clear her name.

Who now can stop difficult MPs demanding greater transparency, particularly when it comes to the Windsors’ finances?

Who believes that, with the US Congress poring over Epstein’s emails, there isn’t still more appalling material about Andrew and his spendthrift ex-wife Fergie to be exposed?

We are in a new world. The genie is out of the bottle and won’t be put back in.

The attempt to call a debate in parliament, for example, broke the longstanding convention that MPs would not scrutinise the monarchy in public.

That the chairman of parliament’s influential Public Accounts Committee should write to the King asking for details of Andrew’s lease on his home at Royal Lodge was another extraordinary development.

Thanks to Andrew, a boundary has been crossed and nothing will or can be the same again.

To borrow a comparison from astronomy, our monarchy been dragged across an ‘event horizon’ – the boundary of a black hole beyond which gravitational pull is so powerful that nothing, not even light can escape.

Andrew has exposed a wasteful, entitled, secretive, lying, self-indulgent version of monarchy no one wants or will tolerate – and has pulled the royal family towards the black hole of oblivion.

He has created a new hunger for accountability and invited Parliament into the affair of the royals.

Charles understands the dangers all too clearly, which is why he has acted so decisively.

Prince William, too, has made no secret that the monarchy must adapt and has said that further change will come when he is King.

In his recent interview with Canadian actor Eugene Levy on his Apple TV show, The Reluctant Traveller, William was clear: ‘I don’t fear it. That’s the bit that excites me, the idea of being able to bring some change.’

But here we need to ask what sort of developments the Prince of Wales has in mind.

It’s no secret that William cannot stand the more theatrical side of the Royal traditions, the medieval costumes, the pomp and circumstance.

Yet, if sitting back and doing nothing would be fatal to the royal family, I would warn William that there are dangers, too, in overhasty change.

Continuity with the past is the essence of our relationship with monarchy. It is why we invited the Stuart kings back to the throne after the catastrophe of the puritan revolution.

With the return of Charles II in 1660, we reclaimed the past. We don’t want to lose it now.

William might feel uncomfortable with old fashioned rituals in dusty churches, but British people love these things – and they matter.

I was reminded of the day that John Bercow became the Speaker of the House of Commons.

Ever keen to cut a dash, he had made the decision to abandon the traditional robes of the Speaker and certainly had no intention of wearing a wig like his male predecessors.

So, when Bercow stepped into the chamber to take the chair in June 2009, he did so in a lounge suit. It was double-take moment.

Without the protection of those historic robes, Bercow seemed no more than a small, rather vulnerable man devoid of the protection and respect his great office deserved.

And his years attempting to command the most boisterous parliament in the western world were undoubtedly more troubled as a result.

So, much as reform of the monarchy is needed, I would urge William to leave the traditions alone.

William’s focus should be on those aspects of royal life vulnerable to attack from the public and Parliament.

Should Harry retain his title as a prince? What royal costs should be funded by the public purse? Should there be a more significant division between working and non-working royals?

These are the real questions – and Prince William must find answers before others do because the point of no return is already behind him.

Parliament has flexed its muscles and there will be those who won’t let it drop.

The dangers that lie ahead are not to do with our great traditions, cloaks, stockings or plumed hats. The perils lie within.