By Daniel Michaels

BRUSSELS -- The argument between President Trump and his Ukrainian counterpart at the White House sent relations between the two countries into a tailspin. It also caused serious damage to an alliance at the heart of the post-World War II order: NATO.

Trump staked out a position that many European allies saw as siding with Russia's autocratic leader, Vladimir Putin, by dismissing the security concerns of a friendly country in need of Western help. He said Ukrainian President Volodymyr Zelensky was losing the war and had "no cards."

The American president's embrace of Russia, an adversary that has worked for years to undermine U.S. global leadership, runs counter to decades of Western policy. The U.S. and its allies founded the North Atlantic Treaty Organization 75 years ago as protection against Soviet Russia.

NATO is based on the idea that the U.S. would use its military might, including its arsenal of nuclear weapons, to come to the defense of any ally that is attacked. That bedrock assumption has now been called into question.

"I worry that we may be in the last days of NATO," said retired Navy Adm. James Stavridis, who served as NATO's supreme allied commander. He said the trans-Atlantic alliance "may not be about to collapse, but I can sure hear it creaking louder than at any time in my long career in the military."

Trump on Sunday wrote on his Truth Social platform: "We should spend less time worrying about Putin, and more time worrying about migrant rape gangs, drug lords, murderers, and people from mental institutions entering our Country -- So that we don't end up like Europe!" Last week, he said the European Union "was formed in order to screw the United States."

The White House on Monday didn't immediately comment on administration policy toward NATO.

The strength of Trump's support for NATO, which he has criticized in the past, remains unclear. At the White House on Friday, he said, "we're committed to NATO" and praised alliance member Poland, which spends heavily on defense. He was less enthusiastic in his support for the high-spending Baltic states, which are also in NATO.

On Saturday, billionaire Elon Musk, a Trump adviser who leads the Department of Government Efficiency, endorsed a post advocating U.S. withdrawal from NATO and the United Nations on his social-media platform, X.

European leaders, who rely on NATO for their countries' security, have refrained from talking publicly about mortal threats to the alliance, but some are starting to talk about alternate plans.

"We want to preserve the trans-Atlantic partnership and our joint strength," German Foreign Minister Annalena Baerbock said Saturday. "But yesterday showed once again that we Europeans must not be naive," she said, referring to events Friday at the White House. "We must take responsibility for our own interests, our own values and our own security, for the sake of our people in Europe."

European leaders met in London on Sunday, pledged to develop a peace plan for Ukraine and dismissed suggestions that Friday's White House meeting had damaged the trans-Atlantic alliance. "I do not accept that the U.S. is an unreliable ally," said British Prime Minister Keir Starmer.

The U.K. and France are leading efforts to develop a "coalition of the willing" that would secure an eventual cease-fire in Ukraine, including by deploying ground troops and military assets. They hope that by doing so, they will manage to convince Trump to contribute to their plan some vital U.S. military resources where Europe falls short, such as in systems for intelligence, surveillance and reconnaissance, command-and-control, air-defense and heavy airlift.

Europe lacks what military tacticians call enablement -- the systems and equipment that enable modern military action -- both for a potential Ukraine operation and Europe's own defense. European NATO members don't have those capabilities due to a mix of their own underinvestment and America's longstanding preference to be in control of such systems. In NATO's traditional division of labor, broadly speaking, Europe was envisioned as contributing the mass of forces while the U.S. would provide sophisticated systems and cohesion for coalition forces.

The current crisis flips Europe's longstanding security dilemma on its head. For years, U.S. strategists fretted over whether they could fend off hostility from Moscow if Europe didn't pull its weight militarily. Now it is Europeans who are in a sweat, wondering if they can defend against Russia without the U.S.

"Europeans are wise to be concerned and to build up their own military industry and capabilities," said Rose Gottemoeller, a former NATO deputy secretary-general and chief U.S. arms negotiator with Russia.

Gottemoeller said concern about U.S. commitment first flared in 2017, at the start of Trump's first term, when he stood in front of NATO's new headquarters building and refused to endorse the alliance's core mutual-defense pact unless Europeans raised military spending.

Since then, European outlays have jumped. Defense Secretary Pete Hegseth on his first trip to NATO's headquarters recently affirmed America's commitment to the alliance and its core tenet of collective security, while still admonishing Europeans to spend even more.

The difference now is the administration's view of threats from Russia. Trump and his team are engaging with Russia, siding with Putin and rejecting traditional U.S. wariness of the Kremlin to a degree unprecedented since World War II -- and by some measures since the founding of the Soviet Union more than a century ago.

Most European leaders, meanwhile, still see Putin's Russia as an existential threat.

A large-scale Russian attack on Europe doesn't appear imminent, but the prospect of an armistice in Ukraine is raising European anxiety. Many of Washington's traditional allies worry that a deal could put Russia in position to rebuild its battered military, economy and global standing without simultaneously boosting European security.

A recent survey of almost 400 European international-security professionals assessing 30 potential high-impact dangers to the EU this year identified a Ukraine cease-fire favorable to Russia as the gravest potential threat on the list. The survey was conducted between the U.S. election and Trump's inauguration.

U.S. isolationism and a withdrawal of its security guarantees to Europe ranked almost on par with a bad Ukraine deal among threats listed -- and comparable to the danger of a Russian nuclear strike, according to the study, led by the European University Institute.

"European worries are confirmed by what we've seen over recent weeks," said survey organizer Veronica Anghel.

European governments are sprinting belatedly to rebuild their militaries, compelled by fear of attack by Russia and abandonment by the U.S. Leaders of the EU's 27 countries will gather in Brussels on Thursday to hash out plans to boost military spending and its ability to handle security challenges independently.

One big catch: The EU isn't a military organization and its work is focused on coordinating members' efforts while boosting Europe's atrophied, inefficient arms industry.

In terms of military action, European efforts fit within plans drawn up at NATO over the past three years, following Russia's large-scale invasion of Ukraine. While European investments will bolster the continent's defenses, they slot into a grand design premised on American participation. The new European equipment and units are part of NATO battle plans and command structures.

Europe has no continentwide military command outside NATO. The U.S. spent decades ensuring that by co-opting or squelching any effort by allied European governments to create rival military groupings. Europeans have repeatedly talked about establishing a multinational fighting force but made little headway.

Now Europeans are pondering what collective defense might look like without the U.S. Talk of defending Ukraine is focusing European thinking on how to establish a command structure not built around U.S. capabilities. The next step would be considering how to defend European territory without relying on American systems.

"If you expect Trump will deal transactionally with Europe or disengage -- or both -- you have to prepare for both," said Giuseppe Spatafora, a former NATO planner and now a research analyst at the EU Institute for Security Studies, the bloc's external-policy think tank.

"How you make up for the U.S. commitment is a political question, and one that must be discussed and acted upon now," said Spatafora.

Write to Daniel Michaels at Dan.Michaels@wsj.com

(END) Dow Jones Newswires

March 03, 2025 10:34 ET (15:34 GMT)

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