From his home in northeast France, 24-year-old student Marc was celebrating Donald Trump's stunning success Wednesday.
Not normally involved in American politics, he has been posting messages about "the saviour of the world" for nearly a year on his "French People With Trump" Facebook group, which has more than 1,000 members.
"There's an awakening a bit all over the world, it's an awakening of the nation state, an awakening of the idea of the homeland," the law student told AFP this week from his home in the city of Lille.
Populist political parties and voters like Marc who share Trump's nationalistic anti-foreigner, anti-elite and anti-globalisation views are nothing new on the fringes of European politics.
But the billionaire Republican's stunning breakthrough will give fresh momentum and hope for their efforts to overturn establishment politicians and traditional parties across the continent.
In France, the far-right National Front (FN) founded in 1972 is at a record high, with polls showing its presidential candidate Marine Le Pen as one of the country's most popular politicians.
Le Pen was one of the first European political figures to congratulate Trump on Wednesday, tweeting that Americans were now "free".
In Britain, voters heeded a call to "take their country back" when they opted in June to withdraw from the European Union in a historic rejection of post-World War II integration on the continent.
"UK. US. There's plenty of other places. This will not be the last," Trump predicted the day after the Brexit vote.
One of the architects of that shock, Nigel Farage from the UK Independence Party, mused Wednesday morning that he could be offered a job by Trump. "I'm hoping he might do," Farage said.
A wave of grievances
Jeremy Shapiro, research director of the European Council on Foreign Relations, told AFP the rise of far-right populism stems from "fear of change, fear of the outsider and fear of cultural contamination."
Across Europe, from Austria to the Netherlands, Germany and even famously tolerant Scandinavia, once-fringe parties are gaining ground and public acceptance.
Trump's upending of American politics is likely to lead to a re-think about how far they can surf a wave of grievances felt deeply in many parts of the West.
"Trump's victory is a sign that the people of the world want a clear political change," said Beatrix von Storch, one of the leaders of Germany's insurgent right-wing party the AfD, on Wednesday.
Dutch far-right leader Geert Wilders, an Islamophobic frontrunner in parliamentary elections due next year, told Trump on Twitter that "your victory is historic and for all of us!"
Trump has other admirers in power, too, including Hungary's Prime Minister Viktor Orban and the Czech President Milos Zeman.
Dubbed "populists", each group in this network is different but shares many characteristics, analysts say.
Their supporters rail against "political correctness". They are likely to live in the countryside or small towns. They see open trade and globalisation as a rigged game for the rich.
Widening inequality and wage stagnation in wealthy countries have fed the anger of these core voters -- mostly low-skilled whites who worry about mass migration and terrorism.
"Immigration is the single most important vector because it is so culturally visible and so immediately threatening," says Shapiro.
This has led to a clamour for drawbridges to be pulled up.
In a time of uncertainty, a strong state with secure borders seems the best defence against a fast-changing world. Protectionism is cast as the antidote to decades of globalisation.
John Judis, the author of the recently published book "The Populist Explosion", says that recession, debt and wage stagnation since the global financial crisis of 2007-09 have created fertile ground.
"Once you get a combination of a downturn and rising inequality then you get a lot of resentment directed upwards," he told AFP.
Many observers including Shapiro see the return of nationalism as an inescapable consequence, a direct challenge to the ideological foundations of the European Union.
It could also spell trouble for other international institutions.
Trump made repeated attacks on NATO, the cornerstone of Western military cooperation, and dismissed the World Trade Organisation.
EU President Donald Tusk alluded to the dangers of isolationist forces being unleashed when he warned that Brexit could lead to the "destruction of not only the EU but also of Western political civilisation."
Conventional wisdom holds that far-right populism should be seen as a warning sign, a trigger for mainstream politicians to pay attention to the grievances of a section of the population.
French student Marc wants nothing less than wholesale change.
The political class "is in total denial," he says. "They have an idea of the world which is completely different to ours."