On the night of the US election, Florian Philippot, the closest adviser to the French far-right leader Marine Le Pen, was watching the results from his apartment on the Left Bank in Paris. Before dawn, when Donald Trump’s victory was not yet official but the liberal establishment was beginning to panic, he tweeted: “Their world is crumbling. Ours is being built.”

Around 8am, Philippot phoned Le Pen to discuss the good news. She was in a jubilant mood at the headquarters of her party – the nationalist, anti-immigration Front National – preparing to deliver a speech congratulating Trump. His victory, on promises of trade protectionism and the closing of borders, looked like a major boost to her presidential campaign. Meanwhile, a car arrived to take Philippot, the party’s vice-president, to the village of Colombey-les-Deux-Eglises, 250km from Paris, to lay a wreath at the tomb of France’s great postwar leader, General Charles de Gaulle.

Trump’s victory happened to coincide with the anniversary of the death of de Gaulle, who led the French resistance against Nazi Germany. Philippot idolises de Gaulle: his office, which adjoins Le Pen’s, is plastered with de Gaulle memorabilia – one of many things that sets him apart as an oddity in a party that has long regarded de Gaulle as a traitor for allowing the former French colony of Algeria its independence.

Philippot’s elite credentials should have been another strike against him within a party that proclaims its loathing of the establishment. A graduate of the exclusive Ecole Nationale d’Administration, which produces presidents and prime ministers, Philippot didn’t start out in the Front National in the traditional way – driving around the countryside sticking election posters to fences. Philippot is also gay, in a party whose co-founder Jean-Marie Le Pen once called homosexuality “a biological and social anomaly”. And yet, at 35, he has become the voice of the party, its media star, and the first to claim Trump’s victory as a sign of a new world order.

After the wreath-laying at de Gaulle’s tomb, Philippot hosted a dinner for 100 party workers and supporters in a nearby restaurant. At the end of the meal, with crumpled paper napkins strewn across the table, he told his guests that Trump’s win proved that the people were “throwing off their chains”. France would be next, he said, promising that Marine Le Pen would win the French presidential election in May.

“Everything that yesterday was said to be impossible or improbable, has today become highly possible and highly probable,” he said. The polls showed that even if Le Pen reached the final run-off, she could never win, but that didn’t matter. Chants of “Marine président!” rang out around the room. Le Pen would “make France great again”, Philippot promised, and everyone stood up to sing the Marseillaise.

If Le Pen is now the closest she has ever been to the French presidency, it is in large part down to her working partnership with Philippot, whose judgment she trusts so completely that she rarely takes a decision without consulting him. “They have an intellectual bond; they are in complete agreement on basic principles,” said Bertrand Dutheil de La Rochère, an adviser to Le Pen who is also close to Philippot.

It is Philippot who is credited with executing Le Pen’s plan to sanitise the Front National’s image, tone down its rhetoric and widen its electoral support – banishing open expressions of anti-semitism, racism and xenophobia, even if those old obsessions still bubble away under the surface. Philippot’s single-minded mission to control the party line and root out dissenters has led his rivals inside the party to liken him to Robespierre, the ruthless French revolutionary leader.

So zealous was Philippot’s drive to transform the party’s image that he encouraged Le Pen to expel her father, Jean-Marie Le Pen, from the party he co-founded in 1972. If the outspoken, racist, Holocaust-denying 83-year-old Papa Le Pen was a blight on the Front National’s electoral prospects, Philippot styled himself as its salvation. But as the Front National attempts to take the presidency, the adulation, fear and controversy that Philippot provokes have opened new rifts inside the party.

Florian Philippot pays homage at the tomb of his idol, Charles de Gaulle in Colombey-les-Deux-Eglises, in 2014. Photograph: Jean-Christophe Verhaegen/AFP/Getty Images

Since the Front National’s modest beginnings in the 1970s – when Jean-Marie Le Pen was chosen as the face of a fledgling nationalist party whose support ranged from neo-fascist street-fighters to ex-members of the wartime collaborationist Vichy regime – the organisation has been engaged in repeated efforts to repackage itself and broaden its appeal to voters. Philippot and Marine Le Pen’s bid to win power by turning economically to the left and courting a disgruntled lower middle class is just the latest of many rebranding exercises. But within the Le Pen family, cracks are showing. Le Pen’s niece, Marion Maréchal-Le Pen, the party’s 27-year-old MP in the hard-right southern heartlands of the Vaucluse, is a devout Catholic and a fervent social conservative who believes that the party must not soften its message.

The challenge for Marine Le Pen is the delicate balance of broadening the Front National’s appeal without losing its core ideals. The number one reason voters choose the Front National is still its anti-immigration, “anti-Islamisation” message – keeping France for the French. At Le Pen’s rallies, one chant from supporters drowns out all others: “On est chez nous!” – This is our country!

* * *

Philippot met Marine Le Pen in May 2009 on Paris’s far-right dinner-party circuit, where guests discussed national sovereignty and identity politics over home-cooked food and fine wine. At the time, the Front National was mired in one of its sporadic crises. It had haemorrhaged voters to the rightwing Nicolas Sarkozy in the presidential and parliamentary elections of 2007, was so in debt that it was forced to sell its party headquarters, and was forecast to get only 6% of the vote in the European elections the following month. Marine Le Pen hoped to take over the Front National and transform it from her father’s fringe protest vehicle into a group that could one day win power. But in a weakened party still defined by its image of racism and xenophobia, she needed technocrats and policy wonks to develop her ideas.

Philippot was 28, studious and shy, the son of teachers from a quiet suburb of the northern city of Lille. A junior civil servant in the interior ministry, he belonged to the establishment detested by the far-right. He had never voted Front National, but he says that from childhood, he had nursed a passion for French national sovereignty. His parents had encouraged an early fascination with politics by taking him to watch electoral counts and to the childhood home of General de Gaulle. Philippot also had a visceral loathing of the European Union. Aged 11, he burst into tears when France voted for the Maastricht Treaty that paved the way for the creation of a single European currency. “I was really young, but emotionally I’d understood that our coins, francs, were going to disappear and I found that really sad. It was a little irrational and emotional, it wasn’t very political, but I was interested in it. It was the first campaign I really followed,” he told me.

Leaving the eurozone and the European Union was an obsession. At the Ecole Nationale d’Administration, Philippot refused to do the customary internship at any of the European Union institutions, saying: “I consider them to be illegitimate and anti-democratic”, and instead spent four months at the French embassy in Copenhagen. Colleagues said he flinched whenever he saw a European flag flying on a public building in France.

Earlier, as a student at Paris’s top business school, HEC, he had backed the 2002 presidential campaign of Jean-Pierre Chevènement, the former Socialist minister who ran on an anti-EU ticket. Philippot has always denied he himself was ever leftwing. “I’ve never considered myself either of the left or of the right. I always considered that division dead with the end of the cold war,” he told me. He caught sight of Marine Le Pen on a TV politics show in 2007, inveighing against the European Union in the pugnacious style she honed as a lawyer, warning the government to “stop taking the people for fools”. Philippot agreed with everything she said. He had to meet her.

Philippot sought out Paul-Marie Coûteaux, a conservative MEP who had championed the cause of French sovereignty and independence from Europe, and introduced himself at a book-signing. Before long, he was helping Coûteaux with his website. Coûteaux knew that Marine Le Pen was looking for young talent, and invited them both to dinner.

Le Pen described their meeting as an intellectual love at first sight. Soon they were finishing each other’s sentences

Le Pen feared someone with Philippot’s civil service background would make for a very dull dinner companion. But over veal and olive casserole at Coûteaux’s antique-stuffed left bank apartment, she found him charming. Coûteaux, who eventually fell out with both Le Pen and Philippot, described their meeting as pure alchemy. Philippot had pored over Le Pen’s autobiography, gripped by her accounts of how, when she was eight, her home was hit with 20kg of explosives intended to kill her father, and how teachers at school called the Le Pen girls “daughters of a fascist”. He told her: “I admire what you do, I’d like to be useful to you.”

“Things immediately gelled between us, both on a human level and politically,” Philippot told me. “She is very direct, there’s no pretence.” Le Pen described their meeting as a kind of intellectual love at first sight. Soon they were finishing each other’s sentences.

“I think there was instantly a real ideological closeness between them,” said Jean-Yves Le Gallou, a veteran far-right thinker and civil servant who had quit the Front National in the 1990s and later worked with Philippot at the interior ministry. Le Gallou was the only colleague Philippot told of his meeting with Le Pen – and the only one who knew about his intense and secretive role as her advisor for two years while he was still a civil servant. Apart from the fact that it was against the law for him to keep his ministry job and work for a political party, he had to consider the FN’s toxic reputation.

‘Marine Le Pen described their meeting as an intellectual love at first sight. Soon they were finishing each other’s sentences.’ Photograph: Chesnot/Getty Images

In 2009, the twice-divorced Marine Le Pen was living outside Paris, with her three children and several bengal cats, in a converted stable block on her father’s estate. The Front National had always been run as a family affair – Jean Marie Le Pen’s three daughters grew up steeped in the party, married men who were linked to the party, and worked for the party. Marine, the youngest, most resembled her father in looks and character. Her current romantic partner, Louis Aliot, is a senior party figure.

Into this tight-knit clan, Florian Philippot arrived as a slightly awkward outsider – ambitious and opinionated. He was a regular fixture at Marine Le Pen’s home, invited for evening or weekend brainstorming sessions over tea and cake, or drinks. He had a particular ability to write fast, in-depth briefing notes and analysis, preparing what Le Pen would say in TV appearances and debates. In person, Philippot has the manner of an intellectual attack-dog – on guard, instinctively wary. Even when he’s going through the motions of politeness, he rarely lets his guard down. The only time he looks relaxed is when he’s sitting next to Le Pen.

Marine Le Pen and Philippot set about drawing up a new party line for when she would eventually take over from her father. Jean-Marie Le Pen had caused a political earthquake in 2002, when he made it through to the second round of the French presidential election. She remembered watching in dread as hundreds of thousands of demonstrators took to the streets in protest, and later voted for Jacques Chirac, in order to keep her father out of office. She could see his mistakes. She understood the need to distance herself from the antisemitism that had long been a feature of the Front National and knew how important it was to bring the party in from the margins. Her father hadn’t wanted real power. She did.

For Marine Le Pen, the model lay in northern France. Aged 30, she had been elected as a regional councillor in Henin Beaumont, a depressed, former coal-mining town. She recognised that France’s northern industrial belt, which had traditionally voted left, could turn to the Front National if the party stood not just against immigration, which remained its chief selling point, but for the victims of deindustrialisation and the financial crisis. Growing up in the north, albeit in a nice house near a golf course, Philippot also knew of the vast number of potential votes to be won among the working and lower middle-class – people with a job, maybe a house, people who were afraid of losing what they had worked hard to achieve and of slipping down the social scale.

Le Pen and Philippot drew up a programme focused on protectionism, a strong state, price control, retirement at 60 and increases to salaries and pensions. It was a manifesto that the Socialist president François Hollande would later liken to a “Communist tract of the 1970s”.

They made no concessions on immigration, but Le Pen changed the emphasis, focusing instead on what the party termed the “Islamisation” of French society. They kept the Front National’s central doctrine of giving preference to French citizens in jobs, housing and welfare. But Le Pen and Philippot rejected the label “extreme right” and sought to repackage the party as neither right nor left.

In a party that under Jean-Marie Le Pen had been all about gut intuition, Philippot introduced a new reliance on data and statistics. He was well versed in voting trends: his older brother Damien worked for Ifop, one of France’s biggest pollsters. (When Damien finally left his polling job last year, it emerged that he had been present behind the scenes of the Front National for years.)

Philippot’s ministry colleague Jean-Yves Le Gallou recalls, that in 2010, at the start of Philippot’s working relationship with Le Pen, she compared Muslims praying in the streets to the Nazi occupation. For this, Le Pen was tried for and cleared of inciting religious hatred. “I was very struck when he said to me at the time: ‘My brother and I have told Marine: ‘Don’t start that again, or we’ll quit,’” Le Gallou recalled. “He did seem to exercise a certain control over Marine’s language from that period.”

In January 2011, when Le Pen finally took over the leadership from her father, Philippot’s role was not yet public. That spring, at a press breakfast on a barge on the Seine, Le Pen finally pushed him into the limelight – although under a false name – introducing him to journalists as the bright young spark who had helped write the party’s economic programme.

Jean-Marie Le Pen’s home in western Paris. His daughter, Marine, lived for a while in a converted stable block in the grounds. Photograph: Matthieu Alexandre/AFP/Getty Images

For someone who now has such a high public profile, it was a lacklustre first showing. “He arrived sweating, he was really stressed,” recalled Abel Mestre, then the Front National correspondent for Le Monde. “He had a computer and slides and gave out CD-Rs. It was very academic, nebulous, no one understood. The economic journalists asked questions. He didn’t reply, she replied for him. It was a fiasco … At that stage everyone was wondering who her campaign director for her 2012 presidential bid would be. Journalists were saying, ‘Imagine if it’s that bloke from the breakfast, wouldn’t it be hilarious?’ And later she announced it was. We were stunned by the choice.”

When Philippot became director of Le Pen’s 2012 presidential campaign, he had only been a card-carrying member of the party for a couple of months. But after her strong showing in the first round, in which she won more than 6m votes and came third, Marine Le Pen was in no doubt about who had made the difference. She made Philippot the most powerful among her several party vice-presidents, in charge of strategy and communications. He was 31.

Philippot’s transformation was staggering. He went from a behind-the scenes intellectual to a highly public figure, dressed in a sharp navy suit and thin black tie. Since 2012, he has regularly appeared on politics shows and rolling news programmes, delivering his tightly controlled party message. From the start, he rarely passed up a chance to be on TV or radio, where he is fluent, defiant, never tripping up, withering and ferocious in his put-downs. Soon he was receiving 15 to 20 requests a day. “I had complained that our party wasn’t getting invited on television enough, so I could hardly then turn them down,” he told me. He is always in motion, constantly checking his phone.

He was also a constant presence at Le Pen’s side, exchanging knowing looks and jokes with her, leaning in to whisper in her ear. He was likened to an old-fashioned courtier, but those who feared his ambition nicknamed him Philippot the First. “If a journalist didn’t write what he wanted, he would blacklist them and stop taking their calls,” said Abel Mestre from Le Monde.

In the 2014 European elections, the Front National topped the poll with 24% of the vote. Since then, it has claimed to be the “biggest party in France”. It had expanded its voter base with working-class voters, public-sector workers and young people – all gains attributed to Philippot.

He’s not someone who shows emotion, or affection. He’s quite austere, cold and distant, he only wants to speak to Marine A senior party official

His successes within the party and the media, however, did not translate to the campaign trail. In 2012 Philippot failed to be elected as an MP in the north-eastern former mining town of Forbach, on the German border. He later lost a mayoral election in the same town, but did eventually take a seat in the European parliament in 2014, and a seat on the regional council for Grand Est the following year.

“In politics, to succeed you have to make yourself feared, and you have to make yourself loved,” Jean-Yves Le Gallou said. “I think he makes himself feared in the party, but I’m not sure he knows how to make himself loved.”

“He works with his door shut in a setting where everyone works with their door open,” said one senior party official. “He’s not someone who shows emotion, or affection. He’s quite austere, cold, and distant, he only wants to speak to Marine. But when you get beyond that, when he is prepared to go beyond that, he can be good company.”

Just before Christmas 2014, Philippot was outed by the celebrity magazine Closer, photographed on a city break to Vienna appearing to hold hands with a television journalist in his 30s. Philippot sued the magazine and won one of the biggest invasion-of-privacy payouts in recent years. The timing was awkward. In 2013, hundreds of thousands of people had staged street protests against the Socialist government’s legalisation of same-sex marriage. Marine Le Pen, on Philippot’s advice, had not gone out to demonstrate. Instead she let her more religious and conservative niece Marion Maréchal-Le Pen make it her own personal cause.

Marine Le Pen has placed several gay men in senior roles. The gay vote for the Front National has leapt in recent years, since the party began to argue that immigration from Muslim countries was causing a rise in homophobia. But hardliners complain of a damaging “gay lobby” at the heart of the party. Philippot denied it was difficult to be gay in the Front National. He said the party was not homophobic. “Not at all, and I mean that,” he said. “We’re a party that doesn’t care about people’s preferences, their sexual practices or whatever … You’re a French citizen foremost. And the Front National is a very young party: the members, the voters, the candidates are young. This is a modern party.”

But the day after we met, Philippot went to a medieval pageant in his north eastern constituency and dressed up as a knight. True to his old form, Jean-Marie Le Pen tweeted a picture of Philippot in the costume with a homophobic slur on his so-called “gay” outfit.

Philippot did not respond at the time. But two weeks later, standing alone on the edge of a provincial party event, he told me with cold poise: “An insult dishonours the person who made it, particularly if it’s a homophobic joke worthy of a 12-year-old. He should be asking himself some questions.” Jean-Marie Le Pen didn’t stop. In December, he told Le Figaro: “Gays are like salt in soup, if there’s none at all, it’s a bit bland. If there’s too much, it’s undrinkable.”

Philippot and Marine Le Pen called their drive to make the party more palatable to voters “de-demonisation” – implying that it was the political and media elite who demonised the party, not the party itself that was at fault. This rebranding exercise was seriously compromised last year when Jean-Marie Le Pen, who still held an honorary role in the party, repeated his view that gas chambers used to kill Jews in the Holocaust were “merely a detail in the history” of the second world war. A bitter family feud ensued, and encouraged by Philippot, Marine Le Pen expelled her father from the Front National.

It was a painful decision, and now father and daughter no longer speak. But Philippot stands by it. Things “could have happened differently”, he said, if Jean-Marie Le Pen had “truly accepted the handover of power to his daughter.”

“I didn’t come into this party saying I’m going to go to war against Jean-Marie Le Pen … I never had any animosity towards him,” Philippot told me. “But he was increasingly out to provoke, and his behaviour became untenable.” Le Pen for his part said in a radio interview that he wished his daughter no longer bore his name, adding bitterly that she should “marry her live-in lover – or maybe she should marry Philippot”.

Marine Le Pen, Jean-Marie Le Pen and Florian Philippot at the Front National summer youth congress, in 2014. Photograph: APERCU/SIPA/REX/Shutterstock

* * *

On a sunny Saturday last May, on the veranda of a roadside restaurant near the Swiss border, Philippot was holding his latest electoral weapon, Gordon the Whippet, on a red leather lead. Philippot was guest of honour at a weekend “patriotic luncheon” in Doubs, a semi-rural constituency in eastern France that was once a thriving centre of the French car industry. Amid fears of further job losses, the Front National’s share of the vote has steadily grown here in every recent election. Gordon the Whippet was playing an important part in Philippot’s latest drive to broaden party support, by appealing to France’s vast number of pet-owners and animal welfare campaigners, including his next target demographic – women and the elderly. Marine Le Pen had also been posting pictures of herself at home with her cats, cuddling kittens or hugging horses. (Philippot had become a regular visitor to Brigitte Bardot, the 1960s film star turned animal rights campaigner, and Front National supporter. After their first meeting at her Cote d’Azur villa, Bardot had posed for pictures embracing him.)

Inside the restaurant, the atmosphere was festive. Party workers poured wine and served guinea fowl to local supporters, including ex-soldiers, retired teachers, landlords, young mothers and small business owners. Michel, 60, an engineer from a village outside Besançon, on the Swiss border, complained that he had recently seen a woman in a Lidl car-park wearing a niqab, despite a law banning women from wearing full-face coverings in public. “My wife and I are getting older and we won’t be able to defend ourselves. Not only will they invade us, they will want to impose sharia law,” he said.

Philippot’s personal police guard stood watch near the door. Since the terrorist attacks on Paris in November 2015, in which 130 people died, he has been given round-the-clock protection. With the exception of Marine Le Pen, he is the only person in the Front National to be accorded this privilege.

After chocolate parfait, Philippot, in an open-necked white shirt, stood and spoke into a cordless microphone. While Marine Le Pen gives thunderous speeches at vast rallies, he is more of a motivational after-dinner speaker, galvanising the leafletters and canvassers. “Our country is in very grave danger,” Philippot said. He described an apocalyptic vision of France (“our elderly people going through bins outside supermarkets”), with patriots riding to the rescue. Whenever his country had gone through a period of doubt “or nearly disappeared”, he said, France was always able “to drive out the imposters in power and replace them with people who really loved our country.” The audience cheered.

Gordon the Whippet stood to attention at the most impassioned points, quivering with emotion. The dog was on loan from Philippot’s close friend and party ally, Sophie Montel, a veteran Front National MEP who lived in a nearby village. “Florian has imposed structure on a party that was always chaotic, disorganised, doing things at the last minute,” Montel told me.

Hovering around Philippot at the lunch were some of the sharp-suited, well-educated, on-message young staffers that he has recruited and placed across the party structure. An article about them in L’Obs magazine in May 2016 – titled “Help! Philippot has cloned himself” - had particularly pleased him, although the notion that he is creating his own devoted identikit army inside the party has irked his critics. Rather than throwing dinner parties, Philippot sometimes relaxes at theme-parks like Parc Astérix, or rallies his young troops with outings to laser tag. “He gives us a lot of work – he’s really demanding, but if you prove yourself, he trusts you very quickly,” said Thomas Laval, 23. One of Philippot’s proteges, Laval is a student and regional councillor in the north-east and co-president of a Front National party section that recently opened, amid much controversy, at the elite Sciences Po institute in Paris. In November, a student union sit-in blocked Philippot from appearing at a debate there. “Despite the language of technocrats like Florian Philippot, the Front National is still the Front National, a party that’s racist, anti-semitic and extreme-right,” Sacha Ghozlan, of the Union of Jewish students of France, told Le Monde at the protest.

In a party run along clan lines, Philippot quickly saw the importance of building his own trusted inner circle, bringing in his pollster brother, then his father – a former primary school headteacher, who is now a regional councillor in the north.

Although the “Philippot line” dominates the party and his strategy is the foundation of Marine Le Pen’s presidential bid, ideological differences between Philippot and Le Pen’s ambitious niece Marion Maréchal-Le Pen still fester. She is anti-abortion and against same-sex marriage. Philippot believes those issues could scare off new voters and should be left alone.

He dismisses the friction between them as “little differences in leaning”, but there is still low-level sniping. Last year, Philippot dismissed Maréchal-Le Pen’s concerns about same-sex marriage as less important to party members than “cultivating bonsai trees”. Later, in a video filmed at his flat, he talked to the camera with a bonsai tree placed in full view on a table beside him.

‘Ideological differences between Philippot and Le Pen’s ambitious niece Marion Maréchal-Le Pen (pictured) still fester and could complicate the presidential campaign.’ Photograph: Jean-Francois Monier/AFP/Getty Images

In the eastern city of Metz, near the German border, at the end of May, rain poured into the cloistered courtyard of a 17th-century abbey. Local politicians were gathered in a council chamber in the basement, thrashing out the €2.5bn budget for the Grand Est region. Stretching from the vineyards of Champagne down through Alsace-Lorraine, the area, comprising 5.5 million people, is bigger than some European countries.

The French regional elections in 2015 were a turning point for the Front National. The party topped the first round with 28% of the vote. Mainstream parties warned the “antisemitic and racist” party would bring France to its knees. The left withdrew in key areas, joining with the right to stop the Front National winning control of any region.

Since his election as a regional councillor, Philippot now leads the biggest opposition party on the Grand Est council. But as the regional assembly – run by the centre-right Républicains party – discussed the crucial budget for high schools, transport and local investment, his seat in the chamber was empty. He was 300km away in a Paris TV studio, on one of France’s most popular morning politics shows.

The session began without him. It was a gift for his regional opponents, who call him a carpetbagging Paris opportunist with no real local ties.

“While we’re waiting for our extreme-right colleague, let me just say I’m so happy that this region isn’t run by the extreme right,” smiled the Socialist party deputy Pernelle Richardot. The Front National councillors, furious to be called “extreme-right,” erupted in rage and began angrily banging on their desks and shouting in protest.

Four hours later, fresh off the high-speed train from Paris, Philippot took his seat, as if nothing had been amiss. Within minutes, a councillor for the Républicains called the Front National “extreme right” once again. Philippot narrowed his eyes and leaned into his microphone: “I demand that the session be suspended so the elected member can take time to reflect on the seriousness of what he has just said.” Philippot stood up and stormed out, with his 45 councillors following in single file. “Ooh, he’s angry,” shouted a grinning councillor from the Socialist benches, rubbing his hands gleefully.

After nightfall, when the assembly session seemed like it would never end, a Front National councillor made a provocative suggestion – that the names of all people listed on the intelligence services’ confidential “S-files” of individuals believed to have been radicalised should be flagged to high schools who could check if any were on their staff.

“In a certain period of our history, we put yellow stars on people. You’re not far from that with your S files!” shouted a member of the Républicains. Metz, on the frontline of first and second world wars, is extremely sensitive to any reference to the Nazi occupation. Hearing his party likened to the Nazis, Philippot got up, and stormed out of the chamber, once again followed dutifully by his councillors.

“I do it systematically,” he explained in the corridor. “Each time they call us extreme right, I walk out. It’s insulting to us, and even more so to our voters.”

Yet these repeated protests did seem time-consuming. And failing to turn up in the morning had made him an easy target for his critics. “It’s the first time I haven’t been here,” he said and shrugged. “They need me, they’re lost without me.”

The night Britain voted on whether to leave the European Union, before the polls had even closed, Philippot hosted a Front National Brexit celebration dinner at a Parisian bistro. Marine Le Pen was there, smiling and laughing, eating fish and chips and waving French and British flags.

Philippot later said that there were two key moments in his life when he cried – when his mother died in 2009 and his tears of joy when Britain voted to leave the EU.

“To see something happening in a major European country, which is exactly what we’re proposing for France, we’re thrilled,” he told me the morning after the vote. Brexit was a vindication of his own strategy. To radical right parties across Europe, globalisation was failing and the nation state was back.

This month, Philippot addressed a meeting of party workers in l’Oise, in the northern Picardy heartlands where the Front National’s popularity is rising. “A majority of French people think like us,” he said. But more than half of French people still view the party as a danger to democracy and only one-third believe that it is capable of governing. Le Pen’s campaign, which begins in earnest in February, will depend heavily on Philippot’s claim that he can neutralise hostility and win over reticent parts of the electorate.

But for some, softening the Front National’s message will not help the party to win. “He has set out to pasteurise the discourse, but it wasn’t a pasteurised discourse that led to the Brexit and Trump victories,” said the far-right thinker Jean-Yves Le Gallou. “It was the complete opposite.” •

Main photograph: Joel Saget/AFP/Getty Images

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