The "worrying declarations by the new American administration all make our future highly unpredictable," said Tusk, who framed this concern alongside the menace of jihadism and an aggressive Russia. As the specter of Brexit looms over the continent, many leaders are still grappling with Trump's indifference to the European project and other institutions that have guaranteed prosperity and security on both sides of the Atlantic for more than 50 years.
"The Trump administration, like a wrecking ball swinging its way across the Atlantic, pounds into Europe’s strategic assumptions," wrote the Financial Times in a Wednesday editorial. Trump, it added, "is challenging cardinal tenets of U.S. foreign policy in ways that would have horrified all his predecessors since Harry Truman."
Europeans are asking questions they never quite thought they would have to: Will Washington disrupt the global economy? Will it defend Europe against an expansionist Russia?
Earlier this week, Guy Verhofstadt, the Belgian official who is now the E.U.'s head Brexit negotiator, spoke to an audience in London about his recent visit to the United States. "I can tell you that every European I met had drawn only one conclusion, and that is the E.U. has fewer friends than ever in the U.S.," he said.
It certainly doesn't have many in the White House. Trump sided with the pro-Brexit crowd and likened his own presidential campaign to the successful insurgency waged by a coalition of Euroskeptics, populists and xenophobic nationalists in Britain. Verhofstadt pointed to the powerful role of Trump's chief adviser, Stephen K. Bannon, an ethnic nationalist who has made common cause with Europe's far-right.
Bannon is actively working to destroy the European Union, suggested Verhofstadt, and "is sending people now to Paris and Berlin to prepare for similar referendums ... as Brexit."
It should be no surprise that the mood in some European circles is now poisoned against Trump's America. Note the chuckling on Wednesday when Nigel Farage, Brexit agitator and Trump's best friend across the pond, delivered an angry speech against his colleagues in the European parliament, a Trump logo pinned to his lapel.
Farage said European critics of Trump were "anti-American" and "anti-democratic zealots." But most people listening to him were probably paying more attention to another British parliamentarian, Seb Dance, who was sitting behind Farage with a sign that read: "He's lying to you."
"Mainstream politics must be more willing to challenge the nationalists and the populists," said Dance, a Labour politician from London, in a statement afterward. "They pretend to stand up for people who are suffering but their diet of hate, division and suspicion create only misery and poverty."
But so far the specter of Trump isn't banding Europeans together. "Instead of unifying the E.U.," wrote Georgetown professor Kathleen McNamara in Foreign Affairs, "Trump’s apparent Euroskepticism may undermine it by stirring up popular anger against internal enemies: the faceless E.U. technocrats and disdained national elites who seem disconnected from the day-to-day problems of most European people."
Tightening bonds between Russia and the U.S. may force Europeans to unify on some level, but "even if that dynamic materializes," argued McNamara, "its effects might be drowned out by popular demands for political change after years of economic austerity and technocratic leadership."
Indeed, right-wing populists are on the march on the continent. The next battleground will be France — the country will elect a new president in May — and already some of the same forces that propelled Trump to power seem to be aiding far-right candidate Marine Le Pen. After seeking to undermine Hillary Clinton's candidacy last year, WikiLeaks, a whisteblower organization that increasingly seems like a Russian front, this week promoted thousands of documents about Le Pen's main rival, Francois Fillon.
Whatever the case here, the Kremlin does have real ties to a number of European far-right and populist parties, all of which celebrated Trump's election win.
The editorial in the Financial Times, the paper of pro-E.U. elites, called on "Europe to take more responsibility for its security" and to aggressively "persuade internationalists" in Washington of the importance of the relationship. But they still have to reckon with the discontent and ennui of their own societies.
So the Tusks and Verhofstadts of the world face a steep climb ahead. They may find some moral support from the other great institution of Europe — the Vatican — which made its first public remarks on Wednesday regarding the American president's controversial executive orders.
“Certainly there is concern because we are messengers of another culture, that of openness,” said Archbishop Angelo Becciu, a top Vatican official, when responding to reporters. "We are builders of bridges, not of walls."
And there are still voices of dissent in Washington. On Wednesday, retired Gen. David Petraeus, who had a brief flirtation with Trump over the secretary of state post now taken by former Exxon CEO Rex Tillerson, articulated what could be read as an attack on the White House's "America First" doctrine.
"Americans should not take the current international order for granted," said Petraeus at a House Armed Services Committee hearing. “It did not will itself into existence. We created it. Likewise, it is not naturally self-sustaining. We have sustained it. If we stop doing so, it will fray and, eventually, collapse."
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