President Trump's evolving foreign policy stresses that U.S. interests come first. His manner of seeing to that, however, is having mixed and perhaps counterproductive results.
Trump's focus on "America first" as a prism for global security, diplomacy and trade has meant questioning or downgrading decades-old strategic alliances and long-held policies, from NATO to Latin America.
While institutional constraints may prevent too radical a shift, the new White House priorities could undermine U.S. global influence, say numerous current and former diplomats. Some allies, especially in Europe, already say they no longer look to the current White House for moral authority or leadership on the world stage.
During his first official trip abroad, the president aligned himself with autocratic leaders such as Saudi Arabia's King Salman and Egypt's Abdel Fattah Sisi, even as he clashed with the elected leaders of European nations with which the United States traditionally has shared core values and interests.
Trump now is considering withdrawing from the Paris climate accord, a landmark environmental agreement, signed by nearly 200 nations, meant to reduce greenhouse gases and curb global warming.
Since the end of World War II, Democratic and Republican presidents have broadly supported similar foreign policies: a strong commitment to allies, belief in free trade policies, and leadership in the world — in contrast to the isolationist movement that briefly emerged in 1940, the last time an "America First" movement was in fashion.
"To throw all of the commitments of the last several decades into question, as [Trump] did with his outright bullying of the Europeans, and now, if he does pull out [of the Paris accord], then we are looking at a real weakening of the leadership and credibility of the United States in the world," said Nicholas Burns, former U.S. ambassador to NATO under President George W. Bush.
During last week's summits of the NATO military alliance and the Group of Seven top industrialized nations, Trump dismayed officials in Germany and France, among other allies, when he failed to embrace Article 5 of the NATO charter, which essentially states that an attack on one member is an attack on them all.
It has been invoked only once — when NATO formally joined the United States in Afghanistan after the Sept. 11, 2001, terrorist attacks.
"The absence of that expression of unconditional support for NATO security from a U.S. president could send a shudder of doubt into the hearts of statesmen and politicians whose futures, whose lives, depend on the strength of American resolve," said retired Gen. Wesley Clark, who served as NATO supreme commander in the late 1990s.
Trump also repeated his demand that other NATO members spend more on defense. Only five of the 28 members meet the current NATO target of 2% of economic output, although several have boosted military spending in recent years.
He also refused to commit to the Paris climate accord, which is broadly supported in Europe and China. Trump at one time called climate change a "hoax," and some of his advisors argue that reducing U.S. greenhouse gases is too costly whatever the science says.
Trump also has downgraded human rights, parting with many of his predecessors. He did not bring it up publicly with leaders of Arab nations, such as Salman and Sisi, that allow no elections and severely restrict freedoms of religion, assembly and the press.
The reactions to Trump's priorities were sharpest in Europe.
Without mentioning Trump by name, German Chancellor Angela Merkel said at a campaign event this week that the era in which Europeans could "rely on others" is over.
Germany's foreign minister, Sigmar Gabriel, suggested Trump was putting European peace in danger.
"Anyone who accelerates climate change by weakening environmental protection, who sells more weapons in conflict zones and who does not want to politically resolve religious conflicts is putting peace in Europe at risk," he said.
France's new president, Emmanuel Macron, walked past Trump at one point to effusively greet Merkel.
Days later, when Russian President Vladimir Putin visited him in Paris, Macron criticized Russia's human rights record and blasted Moscow for meddling in the recent French presidential election.
The contrast with Trump, who has not criticized Putin despite the conclusions of the U.S. intelligence community that Russian intelligence interfered in the 2016 presidential campaign, was notable.
The White House spokesman, Sean Spicer, painted a different picture of what happened in Brussels and Sicily.
"He views not just Germany, but the rest of Europe, as an important American ally," Spicer told reporters Tuesday. "During his conversations at NATO and at the G7, the president reaffirmed the need to deepen and improve our trans-Atlantic relationship."
This is hardly the first administration to disagree with European allies. In the 1970s, President Nixon's envoys threw their weight around over a strong U.S. dollar at a time some European currencies were weak.
And President Obama, like many of his predecessors since the Cold War, had demanded NATO member states pay more for joint defense.
Lanhee Chen, a veteran of GOP presidential campaigns who has been critical of Trump policies, said he is willing to give the president's foreign policy the benefit of the doubt.
"One diplomatic faux pas will not fundamentally shift the trajectory of the [European] relationship," said Chen, a research fellow at Stanford University's Hoover Institution. "Elements of the relationship were built up over many years."
But diplomats and numerous European leaders say the dynamics seem different now.
Trump "has revolutionized our ideas of what the U.S. stands for," Martin Wolf, chief economics columnist at Britain's Financial Times, wrote Wednesday. "We live in the world the U.S. made. Now it is unmaking it. We cannot ignore that grim reality."
For one, Trump's praise for Putin in the past has unnerved Europe. NATO, after all, was created to serve as a bulwark against Russian aggression. Undermining NATO may encourage Moscow to increase pressure on former Soviet republics.
The downshift in U.S. influence is most worrying, according to Burns, the former U.S. ambassador. Quitting the Paris climate deal, for example, would cede leadership to China, a mind-boggling development for many veteran American diplomats.
Trump already has pulled out of the proposed Trans Pacific Partnership, a 12-nation trade agreement meant, in part, to provide a counter to China's growing influence in Asia.
"If we retreat on the responsibilities we have, that's a real danger," Burns said. "If we pull back on U.S. leadership, how can we be effective?"
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