Patrick Semansky / Associated Press

Two-plus years into the Trump presidency, NATO is learning to live with the United States president, and vice versa. NATO Secretary General Jens Stoltenberg has been praised for his deft touch with President Donald Trump—for making him feel that his concerns are heard while still defending NATO’s value. For his part, Trump has long been skeptical of military alliances, contending that well-heeled nations shouldn’t rely on the U.S. defense umbrella without picking up more of the cost.

“In an ideal world, we would not need to spend any more on defense,” Stoltenberg told a joint session of Congress on Wednesday, displaying his dexterousness. “But we do not live in an ideal world. Freedom has enemies, and they need to be deterred.”

The Norwegian had come at the invitation of House Speaker Nancy Pelosi, to address a legislative body that has expressed overwhelming support for NATO —even as President Trump has criticized its members over defense spending and shaken long-held assumptions about America’s commitment to the alliance. Stoltenberg, having praised the alliance for safeguarding peace in Europe, and having thanked America in particular for its contributions to the cause, echoed the president’s message: “NATO allies must spend more on defense. This has been the clear message from President Trump, and this message is having a real impact.”

Meanwhile, the alliance faces an expansionist Russia determined to divide it. The more points of tension develop, the more opportunities Russia could have to exploit them.

Stoltenberg, twice Norway’s prime minister and the head of NATO since 2014, ticked off a list of those disagreements in his speech: over trade, energy, the Iran deal, and climate change. He could have added Trump’s sudden decision to withdraw most U.S. troops from Syria; European energy purchases from Russia; creeping authoritarianism in NATO members such as Hungary and Turkey; or Turkish weapons purchases from Russia. Still, Stoltenberg noted that disputes have erupted among NATO members in the past—the French withdrawal from military cooperation in 1966, the divisive Iraq War debates in 2003. And still the alliance is poised to celebrate its 70th year on Thursday. “Open discussions and different views is not a sign of weakness,” he said. “It is a sign of strength.”

Previous presidents have raised the spending issue, though Trump has stood out for the harshness of his rhetoric, including a reported threat at a NATO conference in Brussels last summer to “go it alone” if the allies didn’t pay up. But there’s been a difference between his rhetoric and his administration’s policy. In practice, Trump’s administration has been hard on Russia and supportive of Europe, notwithstanding his stated desire to get along with Russia and his belittling of some European leaders.

“There’s this argument within the policy community about policies versus words,” says Rachel Rizzo, a fellow at the Center for a New American Security who works in its transatlantic-security program. “Trump uses harsh words all the time. It’s something that we’ve gotten used to.” At the same time, she noted that the administration has increased spending on the European Deterrence Initiative, which is aimed at preventing regional aggression. Under Trump, the U.S. has put more troops into the Baltics and eastern Europe. “Our commitment to NATO is strong,” Rizzo says.

The disconnect between words and actions does, however, fuel anxiety over the U.S. commitment to NATO, especially after Trump sparked deep concern in Washington, D.C., and Brussels by initially declining to publicly endorse NATO’s Article 5 commitment to collective defense (he did so halfway through his first year in office). At times Trump has seemed at odds with the pro-alliance wing of his own government. In the summer of 2017, Vice President Mike Pence traveled to Montenegro, a NATO ally, where he reassured Balkan leaders that the U.S. would be a bulwark against Russian aggression. A year later, Trump said in an interview with Fox News that Montenegro is home to “very aggressive people” whose actions could touch off “World War III.”

Another source of tension has been Trump’s decision to withdraw most U.S. troops from Syria, which took European officials by surprise. This was followed up with a Trump-administration demand that the Europeans stay to deal with the aftermath. One European official, speaking on the condition of anonymity in order to discuss the issue, told The Atlantic that when Acting Defense Secretary Patrick Shanahan made this expectation clear at a conference in Munich in February, the Europeans pushed back, saying: We’re in together, and we’re out together. Trump ultimately opted to leave some 400 U.S. troops in the theater.

Trump has been particularly focused on the idea that the U.S. bears an unfair share of the burden to protect Europe—an argument that resonated with his core voters in the 2016 presidential campaign and is part of his broader complaint that the U.S. had been exploited in trade pacts and in a host of dealings with other nations. Europeans have actually been stepping up defense spending since the Russian annexation of Ukraine’s Crimean Peninsula in 2015, although Trump has taken credit for some of the increases, with Stoltenberg’s encouragement. Still, Trump has continued to insist that the allies meet a defense-spending target they all said they’d aim for back in 2014—when each country committed to move toward spending 2 percent of GDP on defense, without specifying a timeline.

Germany has recently been a flash point in this debate, and its struggle shows why defense-spending increases are difficult even for a wealthy country. Vice President Pence met privately with German officials in Munich in February and pressed them to boost their country’s financial contribution to NATO. Trump-administration officials believe that Germany is wealthy enough to comply with the 2 percent goal.

When Pence made his case, his German counterparts balked, citing their own domestic politics, according to a White House official familiar with the matter, who spoke on the condition of anonymity because they were not authorized to speak publicly. And they made clear that it could be years before they were able to raise military-spending levels.

The German position was very much, “Thank you for what you’re doing. We need you to do more because our own domestic politics makes it impossible for us to get there,” the White House official said.

In an Oval Office meeting on Tuesday with Stoltenberg, the president returned to the same sore point: Germany. The country, he told reporters, is “not paying what they should be paying.”

Appearing at a NATO summit meeting in Brussels last year, Trump upbraided Germany for its natural-gas-pipeline deal with Russia. He tweeted: “What good is NATO if Germany is paying Russia billions of dollars for gas and energy. Why are there only 5 out of 29 countries that have met their commitment? The U.S. is paying for Europe’s protection, then loses billions on Trade.”

One Western diplomat, who also spoke on the condition of anonymity because they were not authorized to speak publicly, told The Atlantic that Trump should avoid the appearance of bullying Germany on military spending. Such aggressive messages can boomerang. The diplomat said that “it can actually be harder for Germany to spend more if it looks as though they are bowing to U.S. pressure.”

Apart from that, Trump’s tight focus on the 2 percent goal minimizes other contributions that aren’t measured in financial terms.

“As an example,” the diplomat said, “Greece has met the 2 percent threshold; Denmark has not. However, Denmark has sacrificed a significant amount and has been an invaluable member of the alliance.”

Strains were evident during Vice President Pence’s afternoon speech at an international conference marking the 70-year anniversary. Echoing the president, Pence again took aim at Germany and cautioned that NATO is not a “unilateral security guarantee.”

He received polite applause throughout the 25-minute address from the European and NATO diplomats in attendance. But when Pence sought to celebrate Trump—crediting the president with “resolute leadership” that had strengthened NATO—no one clapped.

Yara Bayoumy contributed reporting.

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