My favorite scene in Mean Girls is when Gretchen Wieners, one of the ghastly trio of vain, self-obsessed, sneaky, gossipy and gutless ‘Plastics’, cracks up during a Shakespeare class and launches into a bitter tirade.

‘Why should Caesar get to stomp around like a giant, while the rest of us try not to get smushed under his big feet?’ she wails. ‘What’s so great about Caesar? Hmm. Brutus is just as cute as Caesar. Brutus is just as smart as Caesar. People totally like Brutus just as much as they like Caesar. And when did it become okay for one person to be the boss of everybody, huh? Because that’s not what Rome is about. We should totally stab Caesar!’

I thought of this as I watched the hot-mic video clip of French President Emmanuel Macron, Canadian Prime Minister Justin Trudeau, British Prime Minister Boris Johnson and Dutch Prime Minister Mark Rutte at a Buckingham Palace drinks reception for NATO leaders last night.

There they all were, sniggering and bitching away like spiteful little Mean Girls about US President Donald Trump, the modern-day Caesar.

My favorite scene in Mean Girls is when Gretchen Wieners, one of the ghastly trio of vain, self-obsessed, sneaky, gossipy and gutless ‘Plastics’, cracks up during a Shakespeare class and launches into a bitter tirade

It was a very revealing clip for many reasons.

First, the pathetic cowardice of them all huddling in a group mocking Trump behind his back like schoolkids who give it the Billy Big Balls swagger about their teacher the moment the teacher’s left the room.

Second, the brazen disrespect they showed to the President of the United States, by far the most important member world leader at the NATO summit.

And third, the unbelievable stupidity of none of them realizing there were TV cameras in the room that might capture their duplicity.

‘Is that why you were late?” chuckles Johnson accusingly at Macron at the start of the video.

Before Macron can respond, Trudeau, swigging from his drink, pipes up with a jibe at Trump: ‘He was late because he (Trump) takes a 40-minute press conference off the top.’

The video cuts to a slightly later clip that sees Macron gesticulating furiously before Rutte exclaims ‘fake news media’ and Trudeau interjects: ‘You just watched his team’s jaws drop to the floor!’

As he says this, Trudeau mimics his own jaw collapsing.

I thought of this as I watched the hot-mic video clip of French President Emmanuel Macron, Canadian Prime Minister Justin Trudeau, British Prime Minister Boris Johnson and Dutch Prime Minister Mark Rutte at a Buckingham Palace drinks reception for NATO leaders last night

There’s lots of guffawing amid all this, all of them thoroughly enjoying having a good old laugh at President Trump’s expense.

And standing right there among them is Princess Anne, daughter of the Queen.

When I saw Anne’s world-famous never-changing hairstyle nodding away in obvious amusement too, something inside me flipped and I found myself mouthing my own words of indiscretion: ‘What the hell are you lot all laughing at?’

This is the same Princess Anne whose brother Andrew wasn’t able to attend the reception because he’s just been fired from public life in shameful disgrace over his support for serial pedophile Jeffrey Epstein.

Just 24 hours earlier, on Monday night, a woman named Victoria Roberts Giuffre wept on the BBC’s Panorama investigative news program as she recounted horrifying details of allegedly being sex trafficked on multiple occasions by Epstein to Prince Andrew when she was just 17 years old.

You’d have thought that might have put a slight dampener on his sister’s willingness to engage in group mockery about the leader of Britain’s most important ally at a public Palace event.

But it didn’t.

The world leaders were sniggering and bitching away like spiteful little Mean Girls about US President Donald Trump, the modern-day Caesar

Trudeau (second from left), swigging from his drink, pipes up with a jibe at Trump: ‘He was late because he (Trump) takes a 40-minute press conference off the top’

I wonder if any of those fearless world leaders around her had the guts to divert from their Trump-scorning long enough to ask if Andrew would now submit himself to an interview with the FBI, under oath, in which he would finally be forced to tell the truth about exactly what he knew, saw and did in the company of one of America’s worst ever sex offenders?

Yeah, right – and pigs were flying past the Palace windows…

As for the leaders, they should probably look in their own mirrors before seeking to make fun of Trump.

Trudeau, the most ultra-liberal virtue-signalling snowflake in global politics – he’s the clown that wanted to abolish the word ‘mankind’ because it’s sexist - just narrowly escaped being booted out of office in the Canadian election after photos emerged of him wearing blackface on numerous occasions.

Like all PC-crazed preachers, he was found to be a shameless hypocrite. He’s also been a distinctly unimpressive Prime Minister.

Trudeau now presides over a minority government, saw his approval ratings crash to 32% this summer, was recently convicted of breaking the country’s conflict of interest laws by allowing a giant engineering and construction firm to avoid a corruption trial, and has mis-managed Canada’s economy so badly that it trails way behind America on every important financial metric.

As a result of this hot-mic chortling at Trump being leaked, the President has naturally been exposed to much ridicule both here in London at the NATO summit and back home in the US where the media’s already reveling in his supposed humiliation. But Trump hasn’t been humiliated at all

In a damning moment during his live press conference with Trump yesterday, Trudeau was directly challenged by the US President to say if Canada was yet paying 2% of Canada’s GDP on defence, as required to be part of NATO. He stammered and blustered, before eventually admitting it pays just 1.4%.

So on balance, if I were Trudeau, I’d pipe down with the Trump taunts.

Little wonder the President today branded him ‘two-faced.’

Macron, if anything, is in an even worse position.

Even the French can’t stand the arrogant condescending pipsqueak, with his approval ratings plunging to under 30% and two-thirds of his countrymen saying they’re dissatisfied with his performance.

The ‘Yellow Vest’ protests, driven by fury at his perceived disregard for pensioners and workers, have ravaged France all year and a devasting national general strike tomorrow could be the biggest for decades.

Macron’s also outraged NATO members by rudely branding the coalition ‘brain-dead’ due to a supposed lack of leadership by Trump.

Yet the truth is Trump’s been NATO’s biggest cheerleader this week - and has been successful in his thoroughly reasonable campaign to make other cheapskate countries pay more of their dues, and for America to rightly pay less of the overall cost of NATO’s bills.

As for Boris Johnson, it’s hard to know where to start with reasons why he should avoid taking the high moral ground with Trump, from his chaotic private life (he won’t even say how many children he has, possibly because he doesn’t know) to racially-tinged comments and downright lies splattered across buses over how much money Britain pays to the European Union.

Yet this hasn’t stopped him treating the President like a piece of brand-damaging gum on his shoe.

Despite fulsome praise and support from Trump since Johnson became Prime Minister a few months ago, he’s tried everything not to be seen with the President this week lest it damage his chances of victory in next week’s UK General Election.

If that wasn’t spineless enough, Johnson’s also ducked various promised election interviews with British TV interrogators – including me! - which compares very unfavorably with Trump’s extraordinary willingness to regularly lay himself bare to the media dogs.

Trudeau, the most ultra-liberal virtue-signalling snowflake in global politics – he’s the clown that wanted to abolish the word ‘mankind’ because it’s sexist - just narrowly escaped being booted out of office in the Canadian election after photos emerged of him wearing blackface on numerous occasions

The President spent more than two hours yesterday alone fielding questions on any topic journalists wished to raise. No other world leader does this, and love him or hate hi – or his answers - it’s impressively transparent.

As a result of this hot-mic chortling at Trump being leaked, the President has naturally been exposed to much ridicule both here in London at the NATO summit and back home in the US where the media’s already reveling in his supposed humiliation.

But Trump hasn’t been humiliated at all.

He’s just had to endure the petty mockery of a jealous bunch of Mean Girls who like to make fun of him behind his back but don’t have the courage to do it to his face.

The real embarrassment is on them, not him.