‘Santino, never let anyone outside the family know what you are thinking. Never let them know what you have under your fingernails. I think your brain is going soft …’

Don Corleone admonishing his son in The Godfather

My grandmother never broke a law throughout her long life, but that did not stop her from agreeing with the most notorious mafia boss in literary history.

Never tell anyone your business, she always said.

It was a rule she rigidly obeyed for 95 years. Privacy was paramount and extended to how she voted, what she thought of her neighbours and what special ingredients she added to her magnificent cheesecakes and sausage casseroles.

Just like Vito Corleone, the fictional mafioso godfather created by the author Mario Puzo, my Nan believed that allowing outsiders a glimpse of your private world was a weakness that undermined and chipped away at the stability and honour of the individual and the family.

Your business is yours alone, the Don said. Photo: Paramount Pictures

She might have been right about that because after the controversial claims made this week by Prince Harry and Meghan Markle, the royal family is now facing the same ruinous future the old-school underworld bosses experienced several decades ago.

After being governed for more than a century by the strict code of Omerta – a southern Italian rule that values silence and a refusal to co-operate with police – the power of many mafia-style organisations around the world began weakening in the 1980s when a younger generation of underlings began cutting deals with the authorities.

Those deals not only exposed the corrupt inner workings of the major crime families. They also revealed all the private feuds, egos, rivalries and petty jealousies that lie just below the surface of every family.

The royals – or ‘The Firm’ as they often privately refer to themselves – also subscribed to their own version of Omerta for much of the 20th century until Princess Diana decided to go public after her failed marriage to Prince Charles.

In doing so, she ripped away many of the brittle scabs that had long disguised the scars and deep divisions within the monarchy.

But the claims by Meghan and Harry in their carefully choreographed interview with America’s Queen of celebrity culture, Oprah Winfrey, are far more damaging.

If true – and why wouldn’t they be given the form shown by so many members of the Royal Family over the years – they have exposed a dysfunctional, cold-blooded institution that should be shut down and consigned to history as an embarrassment that has long passed its use-by date.

Princess Diana and Martin Bashir during the infamous Panorama interview in 1995.

Come on. Did you really gasp with shock at the claim that a suicidal Meghan filled with thoughts of self-harm had been denied psychological support by the palace?

This is a family that has made the concept of a stiff upper lip its trademark, a family ruled by a cold and aloof monarch who has proven again and again to be more interested in preserving the status of the royal institution than improving the questionable mental health of many of her clan.

And were you really taken aback that at least one unnamed royal insider openly expressed concerns about the skin colour of Harry and Meghan’s children by asking “What will the kids look like?”

This is a family, after all, where the most senior patriarchal figure – the gaffe-prone Prince Phillip – has regularly poked fun at darker-skinned races.

“You managed not to get eaten then?” he asked a British student in 1998 who had just returned from a trek through Papua New Guinea.

“You are a woman, aren’t you?” he muttered to a Kenyan woman he met in the 1980s during a gift-giving ceremony.

Prince Philip has a history of racist remarks under his royal belt. Photo: Getty

And who could forget one of his greatest racist Grandpa moments two years later when he warned a group of British exchange students living in China that, “If you stay here much longer you will all be slitty-eyed”.

And let’s not even mention Prince Andrew.

Within seconds of the Harry and Meghan interview going to air, the usual cavalcade of royal sycophants and commentators like Piers Morgan expressed their disgust at such a blatant attack on the monarchy and their disbelief over many of the claims.

They have stuck to their tired old story of Harry being a gullible, awe-struck young man beguiled by a manipulative, publicity-hungry Hollywood starlet.

Meghan Markle in the interview with Oprah Winfrey.

But most of us are a bit smarter than that and when you consider the evidence gathered over the years, how can you not conclude that the royal family is an anachronism not only out of touch with the values of modern society but completely ignorant of them?

Here’s to Harry and Meghan. My grandmother would have been horrified by their willingness to speak so openly.

But this is not a normal family we are talking about.

It’s a venal, arrogant and mean-spirited organisation that has been sucking on the public teat for way too long, fleecing the British people of funds and respect.

It is also an embarrassment to the Commonwealth and it beggars belief that Australia continues to preserve such a petty and self-obsessed business at the apex of our constitution.

The era of Omerta is over.

With their unprecedented exposure of the Royals, Harry and Meghan have made us an offer too good to refuse.

Walkley Award winner Garry Linnell is one of Australia’s most experienced and respected journalists and editors