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Germany is the most populous nation in Europe, the continent's economic powerhouse and the biggest net contributor to the European Union. It has been a close American ally for decades, and the bonds between Washington and Berlin grew particularly strong in the latter years of the Obama administration, with Chancellor Angela Merkel supplanting her British counterparts to take up the mantle of the “special relationship.”

So it was always going to be interesting to see what happened when President Trump's ambassador to Germany, Richard Grenell, finally took up his post. Trump had made clear his antipathy both for Merkel and Europe's centrist establishment, embodied by the liberal political classes in Berlin and Brussels. Grenell, meanwhile, seemed an ideal Trumpist standard-bearer — a former aide to national security adviser John Bolton, a Fox News talking head and an inveterate tormentor of journalists and Democrats on social media.

Grenell's nomination was held up for months over his combative past, and he was confirmed by the Senate only in late April. But it didn't take long for things to blow up once he reached Berlin.

Shortly after he took up his post last month, Grenell tweeted a threat to German companies to respect U.S. sanctions on Iran after Trump withdrew from the nuclear deal with Tehran. Wolfgang Ischinger, a former German ambassador in Washington, chided Grenell. “Germans are eager to listen, but they will resent instructions,” Ischinger said.

This weekend, Grenell raised tensions to a new level. The ambassador gave an exclusive interview to far-right website Breitbart, an organization whose European editions hailed the rise of Trump, scare-mongered over immigrants and Islam and have long railed against Merkel and the continent's political elites.

Grenell seemed to celebrate the populist “resurgence” in various corners of Europe, though he avoided specifically referring to far-right parties. And he seemed to indicate that he wanted to support their continued rise.

“I absolutely want to empower other conservatives throughout Europe, other leaders,” Grenell told Breitbart. “I think there is a groundswell of conservative policies that are taking hold because of the failed policies of the left.” He added that Trump's election had specifically “empowered individuals and people” to shake up Europe's status quo.

In separate nuggets published by the far-right website, Grenell lambasted Germany's policies on migration and its supposedly inadequate military commitments.

The German government offered a muted reaction to the U.S. ambassador's statements. “I hope he will explain what he actually said in the Breitbart interview and what he meant by it,” Peter Beyer, Germany’s coordinator for transatlantic affairs, said to reporters. “In challenging times like these, the U.S.A. and Europe need to firmly stand together to defend common values and interests.”

Others were more blunt. “Grenell isn’t behaving like a diplomat, but instead like a right-wing colonial officer,” tweeted Martin Schulz, the former leader of Germany's Social Democrats, the center-left party in a joint ruling coalition with Merkel's center-right Christian Democrats. “Ambassadors are representatives of their states and not of political movements.”

The timing of the Breitbart interview did Grenell no favors. The article published just as far-right German leader Alexander Gauland likened the Nazi era to a “speck of bird s---" in a speech before members his AfD party, instead championing “more than 1,000 years of successful German history.” Gauland represents exactly the anti-establishment wing in Europe that Grenell seems eager to uplift.

“That an American ambassador, who represents a country that fought to topple the Nazis, would become a water carrier for some of the most retrograde forces in contemporary Europe defies credulity,” wrote Jacob Heilbrunn of the National Interest, suggesting Berlin was within its rights to expel the American envoy.

On Monday, Grenell rejected criticism that he was offering direct support to particular parties in Europe. He tweeted: “I stand by my comments that we are experiencing an awakening from the silent majority — those who reject the elites & their bubble. Led by Trump.”

Grenell did not respond to multiple requests for comment from Today's WorldView. A State Department spokesperson told Politico's Nahal Toosi that “Amb. Grenell clarified his comments via Twitter and noted it is not U.S. policy to endorse candidates or parties. He was making general observations in the interview.”

But many experts didn't buy it. “Simple fact is that the populist wave which Grenell cheers on is dominated by opponents of existing European governments, existing European foreign policy, EU cohesion, and transatlantic solidarity,” tweeted Shashank Joshi of the Royal United Services Institute, a London think tank. “His contrived two-step is unpersuasive and untenable.”

“These kinds of games are precisely how the radical right communicates with its supporters,” wrote Post columnist Anne Applebaum. “Grenell’s hints were intended for Breitbart’s readers: They know this game, and they know that when Grenell says 'empowering other conservatives throughout Europe,' he doesn’t mean that he supports the ruling coalition in the country where he is serving as U.S. ambassador. I repeat: It means that he supports their opponents.”

This is the source of profound unease among America's traditional allies, who have seen the Trump administration throw the transatlantic alliance into question through squabbling over NATO, the axing of the Iran deal and a protectionist offensive.

The shadow of the Kremlin also looms large. This week, Russian President Vladimir Putin will meet Austria's vice chancellor, Heinz-Christian Strache, a far-right, anti-migrant politician who wants the European Union to end its sanctions regime on Russia. Strache is the junior partner in a ruling coalition with right-wing Chancellor Sebastian Kurz, a politician Grenell has called a “rock star” and even invited to an official lunch on Wednesday.

“The American president is deliberately destroying the American world order. I was used to NATO being attacked by the left wing of the Green Party, but not by the American president,” former German foreign minister Joschka Fischer said in an interview with Der Spiegel. “From an economic policy point of view, Trump is challenging Germany's business model, which has been geared toward exports from the very beginning.”

But Fischer also lamented Europe's lack of options. For all their disquiet with Trump and his proxies, Europeans still need to find common cause with the White House as it struggles with competition from China, an epochal migrant crisis and the threat of Russian interference. "What can we do?" he asked. "Given the current balance of power, sometimes all you can do is gnash your teeth.”

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