Amid the grandeur of the Louvre’s first floor, with its marble pillars, gilded wooden panels, and a ceiling adorned with murals, visitors this week encountered an unexpected sight: the most ornate stable door in the world.

This magnificent wrought-iron door, crafted in 1650 and depicting Christ’s ascension to Heaven, was firmly closed.

In front of it stood a plain grey screen and a couple of rather uninterested security guards, with an additional temporary barrier keeping visitors at a distance.

Signs assertively instructed tourists that not only were selfies off-limits in the area, but even standing nearby was prohibited.

“No photos here; keep moving please,” the signs commanded.

It seemed as if the world’s most frequented museum was concealing something it preferred not to show. And indeed, it was.

For directly behind these huge iron doors sits the Galerie d’Apollon, scene of the extraordinary heist which on Sunday morning saw a group of four thieves walk away with £76million-worth of France’s crown jewels.

The raid, which lasted just seven minutes, was astonishing in many ways. Not least in its brazen simplicity. 

There was no need for violence, explosives, or any Mission Impossible-style abseiling kit. Instead, the gang simply drove their ‘monte-meubles’ – a cherry-picker-style vehicle designed to deliver furniture through apartment windows – down a road next to the Seine, before parking on the pavement.

Wearing hi-vis jackets, they laid out some bollards before using the device to access one of the Louvre’s upstairs balconies.

An off-the-shelf angle-grinder was enough to break open the window and enter the Galerie, where electric chainsaws were then used to gain access to display cabinets filled with diamond and emerald-encrusted jewellery that once belonged to Napoleon’s wife, Marie Louise, stepdaughter Hortense and granddaughter- in-law Eugenie.

Video, shot by a frustrated member of staff watching from a separate wing, shows two of the crooks sedately descending from the balcony, in the mechanised basket of the monte-meubles, before fleeing on Honda motorcycles.

‘They’re about to leave,’ says an astonished onlooker in the clip, which emerged on Thursday. 

‘Blast! Try the police!’ says another. Several Gallic swear words are then uttered, at high volume.

It was, as the old saying goes, the perfect crime. For at no point in this extraordinary caper did the gang face any resistance.

Five security guards who were supposedly guarding the crown jewels that morning appear to have decided to run away, on the grounds that they were not properly trained to tackle intruders. 

A CCTV camera which might have alerted museum bosses to the gang’s unauthorised arrival on the pavement outside was facing the wrong way. 

Neither the Louvre’s windows, nor its supposedly secure display panels, seem to have been any match for a few cheap power tools.

Perhaps understandably, Sunday morning’s heist has, therefore, sparked considerable soul-searching. 

On one hand, the nation has been robbed of eight items of extraordinarily valuable antique jewellery – all uninsured – including a tiara containing 24 sapphires and 1,083 diamonds, and a bow-shaped brooch comprising 2,438 diamonds which was made for Eugenie and exhibited at the Great Exhibition of 1855.

This situation would have been somehow worse had the gang not dropped the empress’s priceless crown during their getaway.

On the other, it has suffered a loss that cannot be quantified in financial terms alone. For as the country’s culture minister Rachida Dati (who is herself facing intense criticism over the affair) pointed out this week: ‘The stolen pieces are part of France’s collective memory and heritage.’

Her colleague Gerald Darmanin, the justice minister, put things even more succinctly. ‘We failed and presented a deplorable image of France,’ he told reporters, adding: ‘The French people all feel like they’ve been robbed.’

Visiting the scene this week, the sense of public anger towards the likes of Dati and Darmanin was palpable. 

It’s intensified by the contempt in which president Emmanuel Macron, who has approval ratings of a mere 14 per cent, seems increasingly held by voters. 

Almost no one believes Macron’s bullish promise, in the immediate aftermath of the raid, that ‘we will recover the works, and the perpetrators will be brought to justice’.

Things aren’t helped by the fact that investigations are being led by the president’s 61-year-old chum Laurent Nuñez, France’s Inspector Clouseau-like minister of the interior. 

The one-time career cop seems to have so far made exactly zero progress. And political opponents are now taking pot-shots.

Jordan Bardella, the 30-year-old president of Marine Le Pen’s hard-Right National Rally party, said the raid was ‘an unbearable humiliation for our country’, demanding: ‘How far will the disintegration of the state go?’ Francois-Xavier Bellamy, of the conservative Republicans party, meanwhile, called the heist ‘a symptom of a country that cannot protect its heritage’.

To such critics, the Louvre heist is emblematic of a far wider malaise. 

Like many institutions, in a country whose public finances have for years been in a state of disarray, the management of France’s vast national museum is grotesquely inefficient. 

Despite housing some of the world’s greatest treasures, it offers a visitor experience ranging from shoddy to downright chaotic, while chewing through shocking amounts of public money.

The place last year welcomed 8.7 million visitors (80 per cent of them from overseas). 

Yet its annual budget has in the last decade ballooned from €199million to €323million (£173million to £281million) – meaning that every single man, woman or child who crosses the threshold costs the French taxpayer more than £32.

There are some 2,242 employees, up from 2,100 a decade ago, including no fewer than 1,200 security guards (to put this in context, our National Gallery in London’s Trafalgar Square manages to survive with fewer than 450). 

In a country with some of Europe’s highest employment costs and most Byzantine HR legislation, the wage and pension bills are grotesque.

What this small army does during their 35-hour working week is anyone’s guess. 

But a report by France’s auditing watchdog – the Cours des Comptes – that was leaked following the heist says there have been ‘consistent and persistent delays’ in making the museum’s security fit for purpose.

The report, written this year, suggests management of the Louvre is hidebound by Gallic bureaucracy. 

Efforts to make even basic improvements to infrastructure are routinely delayed by internal studies that can take years if not decades to complete. 

An initiative to adapt the museum for potential fire outbreaks has, for example, been ongoing for 21 years.

Efforts to install CCTV facilities have been similarly frustrated: today, only one-third of the museum – which contains around 33,000 treasures – has surveillance cameras. 

Quoting the report, Le Figaro newspaper said: ‘Because of repeated postponements of the scheduled modernisation of security systems, cameras have mainly been installed only when rooms have been refurbished.’

In the Denon wing, where the gallery targeted by the robbers is located, a third of rooms have no CCTV cameras, according to the report. 

This, remember, is the home of France’s crown jewels. 

Three-quarters of rooms in the museum’s Richelieu wing, which houses a collection of furnishings, tapestries and ceramics from the Middle Ages to the 19th century, are unprotected.

In another memo, leaked in January, the Louvre’s director, Laurence des Cars – who offered her resignation on Wednesday (it was refused by president Macron) – said the museum’s glass pyramid entrance was not properly insulated from the cold or heat. 

Other areas of the building suffer leaks and allow temperature swings which endanger the conservation of artworks. 

To get a sense of the decay, one need only join the endless ranks of tourists processed through its famous glass entrance each day.

Inside, the museum manages to be both astonishingly crowded and extraordinarily dreary, with some of the world’s most beautiful paintings and antiquities housed in surroundings that have not been updated for decades.

Exhibit A, when it comes to inept management, is presentation of the Mona Lisa, surely the most famous painting in the world. 

Leonardo da Vinci’s masterpiece is displayed on a vast blue wall in a room where selfie-taking crowds are funnelled through dystopian barriers resembling an airport check-in queue.

The grim experience of observing this Renaissance treasure was accurately chronicled by Jason Farago, the New York Times’s art critic, in an essay titled ‘It’s time to take down the Mona Lisa’. 

Farago bemoaned the dull presentation of the work, its ‘hideous snake of retractable barriers’ and a gallery ‘that makes the Spirit [budget] Airlines boarding process look like a model of efficiency and offers about as much visual delight’.

While that room is filled with security staff, other parts of the Louvre have barely an attendant in sight. 

And a hefty proportion of those who are on duty appear to spend most of the day scrolling on their phones.

Like their cowardly colleagues who fled Sunday’s raid, they are managed by Dominique Buffin, a career civil servant who was hired as the Louvre’s first female security chief last year. 

This week Right-wing MEP Marion Maréchal described her (perhaps unfairly) as a diversity hire who was promoted as part of a ‘feminisation policy’ rolled out ‘at the cost of forgoing competence and endangering the cultural heritage of our nation’.

Buffin is also facing criticism from the Left. Despite the huge number of security guards on the payroll, and their generous holiday and pension entitlements, trade unions have for months been complaining about being overworked. 

In June, they went on strike over the alleged shortage of personnel.

‘We were shouting from the rooftops,’ Élise Muller, a Louvre security guard and union official, said this week. ‘We can now see how little we were listened to.’ 

Such complaints seem laughable when set against the sky-rocketing budgets laid bare in the Louvre’s recent accounts. Yet precious little of the cash is ever spent wisely.

Responding to complaints about the decline of the Louvre, Macron this year announced that €700million (£610million) will be spent rendering it fit for purpose.

But that work won’t be finished until 2031 at the earliest. And finding the cash may be a challenge. 

Macron’s government has spent recent months trying to find tens of billions in spending cuts to rein in the country’s budget deficit, which reached 5.8 per cent of economic output last year and has debt on course to hit 121 per cent of GDP by 2028.

For every nine civil servants who are actually in work, the State is currently paying final-salary pensions to ten who are retired.

Yet a recent attempt to raise France’s retirement age from 62 to 64 led to widespread street protests and contributed to the departure of Macron’s fourth prime minister in the past year.

Macron also last week lost the head of his Office for Immigration, Guillaume Larrivé, who resigned after a month in the job. 

He concluded that ‘any ambition to reduce immigration’ in a country which boasts 7.7million immigrants (more than 11 per cent of the population) was doomed to failure, given civil service ineptitude.

The waning reputation of France’s leaders was meanwhile crystallised by this week’s imprisonment of Macron’s predecessor Nicolas Sarkozy, who was sentenced to five years for corruptly using funds from late Libyan dictator Muammar Gaddafi to finance the Frenchman’s 2007 election campaign.

As to the Louvre, history suggests that the gang will eventually be tracked down. It emerged yesterday that they had left some 150 DNA samples at the scene. 

The problem is that the jewellery they have pinched will be long gone by the time they are caught. 

Most likely after the gold and silver has been melted, and the precious stones sold on the open market.

That was exactly what happened when detectives nailed the robbers who stole £8million-worth of jewellery from Kim Kardashian in Paris. 

The American influencer was held at gunpoint in her hotel suite in 2016. But when the men responsible were found guilty, not one was sentenced to spend a single day in prison (beyond remand spells soon after arrest).

A country which allows such perpetrators to walk free is a country where gangs thrive.

And so it very much proved at the Louvre this week.