David A. Andelman, editor emeritus of World Policy Journal and member of the board of contributors of USA Today, is the author of "A Shattered Peace: Versailles 1919 and the Price We Pay Today." Follow him on Twitter @DavidAndelman.

(CNN) It was a split decision for moderation in Europe on Sunday, but the balance seemed to tip toward a new fragility for an already endangered European Union -- not to mention a further victory for Vladimir Putin.

In two critical national ballots, Austrian voters dealt a surprise defeat to the far-right candidate for the symbolic post of president, only to be followed by a stunning rebuke for Italy's stylish 41-year-old center-left Prime Minister.

In Italy, Prime Minister Matteo Renzi staked his leadership, and perhaps the country's membership of the EU, on a constitutional amendment to free the nation from the stranglehold of legislative paralysis. He lost.

The winners turned out to be two populist leaders -- comedian-turned-politician Beppo Grillo, who seized on Donald Trump's "drain-the-swamp" chant . "Our movement has some similarities," he boasted. "We became the first political movement in Italy, and the media didn't even realize it."

The other Italian exulting in the victory over Renzi is the equally anti-EU, right-wing politico Matteo Salvini, whose Northern League supporters delighted in holding up photos of their beaming standard-bearer next to Trump.

Sweeping populism?

Sunday's referendum was just the latest blow dealt by the potent forces of populism that seem to be sweeping across the continent, taking special encouragement from Trump's surprise victory last month.

All share, too, a stunning affinity for Russian President Vladimir Putin, who can only be exulting in his attraction to the expanding forces of opposition to the EU in a growing number of EU nations.

Last month, Salvini, who's expressed interest in becoming prime minister of Italy, paid his fourth visit to Moscow.

He'd already curried favor with Putin after becoming one of the first European politicians to visit Crimea after Russia had seized it.

Though a right-wing victory in Austria would have seen a clean sweep for Putin and against EU unity, Italy -- the third largest economy in Europe, after Germany and France -- is by far the bigger prize.

This weekend's balloting is only the first crest of a wave expected across Europe in the first half of next year.

The first victim, last week, was France's socialist president François Hollande, who took himself out of the running for re-election, days after François Fillon swept to victory in France's Republican primary. Either Fillon, or the extreme right-wing National Front leader, Marine Le Pen, now seem poised to seize power in that country next spring.

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Both have trumpeted their friendship with Putin -- Fillon boasting of the billiards he played with Putin in his Sochi villa, Le Pen pledging she'll cozy up to both Putin and Trump in the "interest of world peace." She's already been photographed by Italian paparazzi boogying with Salvini.

Further high-stakes voting will come thick, fast and furious in the new year. Next March, Dutch voters will vote for a new parliament and hence prime minister, with Geert Wilders' far-right, anti-Islamic and anti-immigrant Party for Freedom leading in some polls.

Merkel's challenge

German Chancellor Angela Merkel has already announced she'll stand for a fourth term next fall, but faces a strong challenge from the potent right-wing Alternative for Germany party , a close ally of France's National Front and Britain's pro-Brexit UKIP.

Alternative party leader Frauke Petry sent one of the early messages of congratulations received by Trump after his victory, and an equally confirmed tweeter, she quickly put out a claim that "this night changes the USA, Europe and the world." The party's leadership has also not hesitated to line up behind Putin.

A multitude of forces are bolstering the populist movements taking hold in Europe. Anti-immigrant, anti-Islamic feelings are paramount in many member states. Returning economic power to the people is another issue driving this anti-EU surge.

Without question, the populist movements in each European country are subtly and often bizarrely different. David A. Andelman

Without question, the populist movements in each European country are subtly and often bizarrely different. But most share a common thread: skepticism over the value being returned to the people of their country by a bloated EU bureaucracy, and a desire to capitalize on overtures from Putin and the new Trump regime, which all seem to be espousing similar values.

A headache for Trump?

With Trump's victory, a model for most of these new-wave populists, the President-elect leader must take particular care as to how he deals with these potent new forces.

Negotiating individual tariff agreements with 28 nations in Europe, while facing similar challenges in broad swaths of Asia after opting out of the Trans Pacific Partnership and threatening to pull out of NAFTA in North America, could leave America's trade position in a shambles.

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At the same time, giving a carte blanche to Putin for further adventures on the fringes of Europe and the Russian periphery can provoke critical challenges to a NATO alliance that is already, in some European circles, feeling endangered as well.