Members of the Kosovo Security Force take part in a field exercise in the village of Nashec near the town of Prizren on Oct. 27. (Armend Nimani/AFP/Getty Images)

The surprise triumph of Donald Trump is raising fears of a historic recalibration between the United States and its allies in Europe, threatening to upend the allegiances that became the cornerstone of post-World War II peace.

Few countries are more in the crosshairs than Germany, Western Europe’s most populous nation and the pacifist home to 47,000 U.S. troops. For decades, American power has been a security blanket here. Even as thousands of U.S. troops were redeployed elsewhere, Chancellor Angela Merkel and President Obama forged a bond that became important in tackling various issues, including the Ukraine crisis and the fight against global warming.

Enter President-elect Trump, who threatened on the campaign trail to back away from the North Atlantic Treaty Organization and force U.S. allies to shoulder more of the burden of their defense. Amid concern of a future bromance between Trump and Russian President Vladimir Putin, the victory has put Europe on notice — and bracing for transatlantic divisions potentially greater than the “freedom fries” era of President George W. Bush.

A big question now is whether Trump’s America could awaken the sleeping giant of German might. This nation, weighed down by the horrific violence of Adolf Hitler, has shied away from military strength since the end of World War II. But leading voices here are now calling for a fresh debate on beefing up capabilities and equipment. They join a chorus from Belgium to Finland, where the clamor is growing for a more independent security strategy with the dawn of Trump.

Many far-right parties in Europe are celebrating the presidential victory of Donald J. Trump. (Jason Aldag,Ishaan Tharoor/The Washington Post)

“Europe will have to be prepared to take better precautions itself,” German Defense Minister Ursula von der Leyen told public television.

Trump could pull back from his most radical pledges, and massive obstacles remain before Germany could reemerge as a “normal nation” matching its economic strength with muscle. Public opposition to military power is part of the DNA here. The military is also an atrophied limb, with a 2014 parliamentary report detailing a shocking state of disrepair. Only one of Germany’s four submarines was operational. Only 70 of its 180 GTK Boxer armored vehicles were fit for deployment. Seven of the German navy’s fleet of 43 helicopters were flight-worthy.

Yet a provocative Trump presidency could prove a tipping point for change, including accelerated talks to create a European army anchored by Germany and France. 

In a sense, that new era of European security is already unfolding. Berlin is sending 650 soldiers to Mali next month in an experimental operation to relieve French forces fighting militants affiliated with the Islamic State. Next year, German troops will also stage a deeply symbolic deployment to Lithuania — a nation once brutally occupied by the Nazis — as part of NATO’s mission to counter an increasingly belligerent Russia.

“If Russia reaches a great power understanding with Trump, Germany would need to reconsider its defense,” said Christian Mölling, senior transatlantic fellow at the German Marshall Fund in Berlin. “But defending against whom? Also the U.S.? You open a Pandora’s box.”

As with many Americans, the unknowns of Trump frighten Europe. His foreign-policy plan has been only loosely sketched out. To minimize surprises, envoys from major U.S. allies typically meet campaign advisers to Democrats and Republicans ahead of the election. But countries such as Germany have not been able to secure advance meetings with the Trump campaign, officials say. Trump has also never met key European leaders, including Merkel.

The nascent push for more independence stems also from the fact that many Europeans saw Trump’s election in deeply personal terms — deflating their view of the United States as a serious nation and a bastion of tolerance. Many feel not just shocked but betrayed. Even senior voices in a nation more familiar with the risks of demagoguery than any other are asking whether it may really be wise for Germany to hitch its wagon to Trump.

“Trump is the trailblazer of a new authoritarian and international chauvinist movement,” Sigmar Gabriel, Germany’s deputy chancellor, told German media after the U.S. presidential election. He added: “They want a rollback to the bad old times in which women belonged by the stove or in bed, gays in jail, and unions at best at the side table. He who doesn’t keep his mouth shut gets publicly bashed.”

In the aftermath of Trump’s victory and the vote by Britain to leave the European Union, many across the continent see an old world order crumbling. Europe’s greatest ally could emerge as its chief adversary on climate change, the peace accord with Iran and free trade. German officials, for instance, are already calculating that Trump’s victory means a massive transatlantic free-trade deal — years in the making — is effectively dead. And Berlin will be hard-pressed to maintain European unity on sanctions against Russia if the United States backs away from its own.

Concern is also rising of a possible frost between Trump and Merkel, whom he repeatedly jabbed at on the stump. Many European leaders sent him innoxious congratulations Wednesday. But Merkel dispatched a cautionary note, offering cooperation with the caveat that it be based on “democracy, freedom, as well as respect for the rule of law and the dignity of each and every person, regardless of their origin, skin color, creed, gender, sexual orientation, or political views.”

In fact, some see Merkel — particularly if she runs and wins reelection next year — as potentially filling the gap on the world stage left by Obama’s exit. In a full-circle transition for Germany, she could emerge as the leading champion, and defender, of liberal Western values. 

“All eyes will be on Berlin,” said Josef Janning, head of the Berlin office of the European Council on Foreign Relations. “Merkel appears to be the only pillar still standing.” 

The Germans have for years been under pressure from the United States to increase military spending and contribute more to operations in international conflicts. Even if Hillary Clinton had won, Germans say they expected that pressure to increase. Although German defense spending has recently grown, it is still only 1.2 percent of gross domestic product, compared with NATO’s benchmark of 2 percent. 

Conventional wisdom holds that Germany’s neighbors, particularly France, would fear a stronger military here. But new calculations with Trump as the leader of the “free world” may change that, experts say.

Germans “avoid military conflict, whereas we rather tend to seek it,” said François Heisbourg, a former member of a French presidential commission on defense. “When the Germans display greater willingness to act like a normal power, that actually makes the French quite happy, because they’re acting like a normal country.”

Stephanie Kirchner in Berlin, Michael Birnbaum in Brussels and James McAuley in Paris contributed to this report.