Ludovic Marin / Reuters

During a testy joint press conference at the NATO summit in London yesterday, President Donald Trump and his French counterpart, Emmanuel Macron, argued openly over how the 70-year-old alliance should handle Russia, the Islamic State, and Turkey. When interacting with allied leaders, Trump’s predecessors have generally followed a golden rule: Disagreements with friends are okay—but only behind the scenes, not in public.

Trump, in contrast, seems to relish going after the Europeans in full view of the rest of the world. The on-camera spat with Macron was the latest sign that Trump has brought America’s most important security alliance to the point of crisis. And the president either doesn’t know or doesn’t care what he’s done.

If the North Atlantic Treaty Organization had reached its 70th birthday under any of the previous 12 presidents, the celebration would have occurred in Washington rather than London. The “Washington treaty” was signed in April 1949, at a dark moment in the early Cold War when a Soviet invasion of Western Europe was not a far-fetched possibility. The United States has always been the most powerful NATO member, and every American president until Trump has been the alliance’s natural leader.

Instead, Trump has been NATO’s loudest critic. He has cast America’s military allies primarily as a drain on the U.S. Treasury, and he has aggressively criticized America’s true friends in Europe—democratic leaders such as Macron and Germany’s chancellor, Angela Merkel—even as he treats Vladimir Putin, Xi Jinping, Kim Jong Un, and other authoritarians around the world with unusual tact. He describes the European Union, whose membership overlaps significantly with NATO’s, as a competitor rather than the close global partner it has been to every recent American president.

The not-so-closely guarded secret at NATO headquarters is allied officials are privately relieved that, rather than holding a full-fledged summit over two days, the leaders are holding just three and a half hours of formal discussions. That limited Trump’s opportunities to blow up the proceedings, as he has done in other major meetings with European and Canadian leaders.

I previously served as U.S. ambassador to NATO under George W. Bush. I also served as a National Security Council staffer under George H. W. Bush, and was lucky enough to observe how a master diplomat like him could further American goals precisely by working skillfully with our allies. Holding a big alliance like NATO together takes patience, tact, a willingness to listen, deep knowledge of the issues, and the self-discipline to refrain from fiery public debate. In London, Trump proved once again that he is incapable of this type of presidential leadership. Senior European officials fear that, in a second term, Trump might seek to end U.S. participation in the alliance altogether. (For the record, I am an unpaid adviser to Vice President Joe Biden’s campaign.)

Stung by Trump’s overt criticism, U.S. allies have begun to reciprocate. Macron caused a real stir in NATO when he told The Economist last month the alliance was effectively “brain dead,” given Trump’s sole emphasis on how much NATO costs the United States and his lack of consultation with France on the withdrawal of U.S. Special Forces from Syria, where France also has soldiers.

Rather than try to mend fences, Trump announced new trade sanctions against France on the eve of the summit. Then, yesterday morning, he told the press that Macron’s comments to The Economist were “insulting” to NATO. Trump’s pious defense of the treaty organization sounded less than sincere, in light of his previous statements.

Trump’s most egregious mistake, though, was his failure to support clearly and unequivocally the key provision of the NATO treaty, Article V, which calls on member states to come to one another’s defense when attacked. He has had several opportunities to do so but has hedged each time. This is of major concern to allied leaders, who want NATO adversaries such as Vladimir Putin to know beyond a shadow of a doubt that the U.S. and its allies will defend Estonia or Latvia should Russian forces cross their borders.

Article V has been invoked just once in NATO history, when the European allies and Canada vowed to come to our defense after the 9/11 attacks. On that tragic day—when I was a very new U.S. ambassador to the organization—my NATO colleagues from Canada and Europe called and pledged that they would fight with us to avenge our nearly 3,000 dead. They kept their promises. Each ally went into Afghanistan with us. They and other partner nations have suffered more than 1,000 combat deaths there, with many more thousands wounded. Our NATO allies are still there with us today.

The London summit heralded one welcome change. Secretary-General Jens Stoltenberg announced that NATO allies have all raised their defense budgets for a collective increase of more than $130 billion. That is an impressive sum—and one for which Trump can rightly take some credit.

Yet the fact is that every NATO ally started to spend more on defense following Putin’s annexation of Crimea in 2014. The allies, including Germany, Trump’s favorite scapegoat, deserve the lion’s share of the accolades. Trump must also share credit with Barack Obama, under whose watch this great spending increase began.

In any case, Trump appears entirely indifferent to the clear, decisive advantage over Russia and China that the United States enjoys because of our European ties. We have 28 allies in NATO, as well as treaty allies in Japan, South Korea, and Australia in the western Pacific, who will defend us when our backs are against the wall. This is the great power differential we enjoy with Moscow and Beijing.

The public, fortunately, understands just how important Europe remains to us. In a 2019 Chicago Council on Global Affairs poll, 73 percent of Americans said they support NATO. The great majority of Republican and Democratic leaders in Congress see the alliance as crucial for our future, as well.

Over the next decade, the U.S. will need to continue to contain Russia’s power in Eastern Europe, cope with the terrorist threat in the Middle East and Europe itself, limit China’s increasing presence in Europe, deal with a panoply of cyberthreats, and provide for the defense of our own country from conventional, nuclear, and asymmetric threats. We will be in an infinitely stronger position to manage all this with our allies beside us rather than alone. The president of the United States must lead accordingly.

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