Jonathan Ernst / Reuters

Despite his justified reputation for unpredictability, Donald Trump’s foreign-policy pronouncements have tended to fit a pattern. He is equally prone to exaggerating his achievements as he is to bemoaning what he sees as slights to America. Which may help explain why he is equally prone to trusting Kim Jong Un as he is to mistrusting U.S. NATO allies.

Kim made a vague promise to Trump to “work toward complete denuclearization of the Korean peninsula;” the NATO countries made a vague commitment under Obama to “aim to move towards” a “guideline” to spend 2 percent of their GDP on defense “within a decade.” The former pledge elicited a triumphant declaration from Trump that the nuclear threat from North Korea was over; the latter has been the grounds for firmly worded letters to allies admonishing them to spend more on defense. (Few have hit the 2-percent target, though the agreement that sets this as the goal gives them until 2024 to “aim to work toward” it. There is no timeline set for Kim’s denuclearization.) The New York Times reported what the president wrote to German Chancellor Angela Merkel: “As we discussed during your visit in April, there is growing frustration in the United States that some allies have not stepped up as promised.”

Trump is not the first president to get frustrated over European defense spending. The U.S. spends about 3.6 percent of its gross domestic product on defense. Of the alliance’s 26 members, four others spend 2 percent of GDP or more on defense, a target reiterated most recently in September 2014. (For how the random the 2-percent figure is, read this.)

It’s not clear the U.S. has a well-defined view on which allies need to spend more, however. While Trump’s letter to Merkel urged Germany, which spends about 1.2 percent on defense, to spend more, U.S. Defense Secretary James Mattis said Germany’s spending plan was “right on track.” Mattis had harsher words for the U.K., which spends 2.1 percent of its GDP on defense, writing in a letter to his U.K. counterpart, Gavin Williamson, that unless the U.K. spends more on defense, it risks losing its place as the U.S. “partner of choice.”

Trump’s irritation at shouldering the financial burden of protecting the world is not unique to him. (Obama famously declared to The Atlantic’s Jeffrey Goldberg regarding U.S. allies that “free riders aggravate me.”) But what’s unusual about Trump is that he appears as quick to reject his allies’ assurances as he is to accept those of his adversaries. In the same week that The New York Times quoted Trump’s letter scolding Merkel, he also told Fox’s Maria Bartiromo of Kim: “I made a deal with him. I shook hands with him. I really believe he means it.”

Trump’s reading of ambiguous language in two very different contexts says more about how he views the world than it does about the underlying issues at stake. He has long said that U.S. partners, whether in trade or in military alliances, are taking advantage of it on a range of issues. The ambiguity of the 2014 Wales Summit Declaration that laid out the 2-percent target is irrelevant to this idea. Similarly, he believes his “great chemistry” with Kim will resolve a problem that his predecessors could not. The ambiguity in his joint declaration with Kim is irrelevant to this belief. This pattern of thinking, if restricted to defense spending, could have been a minor irritant in relations with U.S. allies, but taken with recent disputes over trade, climate change, and tariffs it signals a major fracture—if not an outright break—in the trans-Atlantic relationship.

This is especially the case since there’s another adversary Trump seems intent on believing: Russia’s Vladimir Putin. Faced with accusations from both European governments and his own intelligence community that the Russians interfered in U.S. elections on his behalf, Trump has repeatedly said that Putin assured him no such meddling occurred. And his seeming inclination to trust Putin’s intentions could further erode U.S. relations with NATO. Trump is set to meet Putin after a NATO meeting in mid-July, and he appeared to suggest that the U.S. was open to recognizing Russia’s annexation of Ukraine’s Crimea. The Russian takeover of a chunk of a European country understandably alarms leaders on the rest of the continent. It was that invasion, coupled with Russia’s support for breakaway parts of Ukraine, that resulted in tough U.S. and European sanctions on Russia—restrictions that specifically hurt European companies that have vast business dealings in Russia.

European leaders are further alarmed by Russia’s often belligerent actions against former Soviet states, as well as its interference in elections across Europe. The sight of Trump meeting Putin for a second time, exuding a warmth he rarely exhibits for them in public, might well cause European governments to question whether they can count on Trump if Putin threatens them.

There’s another pattern here. As I’ve previously written, Trump appears to get along with the world’s strongmen. He doesn’t seem as impressed with his European partners. And it goes the other way, too. When asked last week about Trump’s message, Charles Michel, the Belgian prime minister, said of the U.S. president’s letter: “I am not very impressed.”

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