With Trump’s Backing Uncertain, Europe Scrambles to Shore Up Its Own Defenses

Russia’s full-scale invasion of Ukraine three years ago convinced Europe’s leaders that they needed to spend more money on defense. On Monday, leaders from across the European Union and Britain will meet in Brussels to debate a vexing question: how to pay for it.

It is a concern made more acute by President Trump’s return to the White House.

The United States is the largest military funder of Ukraine’s war effort, but Mr. Trump has suggested he will rapidly withdraw U.S. financial and military support and leave it to the Europeans. He has also insisted that NATO nations ramp up defense outlays to 5 percent of their annual economic output, a drastic increase from the 3 percent or 3.5 percent NATO plans to make its goal at its next summit meeting this summer.

The United States itself spends only about 3.4 percent of gross domestic product on defense.

With the war, the European Union, which was founded on free trade and termed itself a “peace project,” has become more committed to deterrence and defense. It is now scrambling to expand its defense industries and make spending more efficient and collaborative. Prime Minister Keir Starmer of Britain will attend Monday’s gathering, the first time since Britain left the European Union that a British leader has met with the 27 leaders of the bloc in Brussels.

Part of the debate will be whether the European Union will be able to raise more money to pay for defense through common debt, as it did to fight Covid.

But the issue is thorny: Such joint fund-raising might impede the efforts of member countries to meet the individual demands that the NATO alliance is already making of them in terms of raising military budgets. Of the 27 E.U. countries that will meet in the closed-door session on Monday, 23 are members of NATO.

NATO’s supreme allied commander in Europe, Gen. Christopher G. Cavoli, has already set capability targets for the first time since the Cold War. The American general has given NATO member countries specific requirements for equipment and force levels, as well as instructions on how to respond in case of a Russian invasion.

There is consensus among officials and analysts that Europe lacks crucial elements of defense like integrated air and missile defense, long-range precision artillery and missiles, satellites, and air-to-air refueling tankers that only the United States currently provides. Replacing those systems would take Europe at least five or perhaps 10 years, the analysts say.

European nations also want to reduce duplication. Ukraine, for example, has been sent at least 17 different kinds of howitzers, not all of which use the same type of shell.

As Russia threatens from the East and Mr. Trump’s support wavers from the West, Europe’s leaders agree that they need a plan to both coordinate and expand their military resources. But diverging national interests and competing budget priorities mean that reshaping European defense will be difficult, expensive and lengthy.

And important countries on the eastern flank, like Poland and the Baltic nations, want to do whatever they can to keep the United States engaged in NATO and the defense of Europe.

The summit Monday is a first step. The E.U. leaders will discuss military financing and joint procurement, and be joined by Mr. Starmer and by Mark Rutte, the NATO secretary general. The goal is to hash out priorities, which will inform the continent’s top diplomat, Kaja Kallas, and its new defense commissioner, Andrius Kubilius, as they work to draw up a more concrete plan, especially for weapons production.

The meeting also has symbolic importance, defense analysts said, as a demonstration that Europe is taking seriously a long-term threat from Russia and the need to reduce its military dependency on the United States.

“This is critical for Europeans,” said Alexandra de Hoop Scheffer, acting president of the German Marshall Fund, a think tank. “They don’t have a choice, because war is taking place on their own continent.”

Deterring Russia, which wants to split the United States from NATO and divide both the alliance and the European Union, is “a generational struggle,” she said. “But our political leaders have failed to explain to a younger generation why the alliance is important and why it’s important for Ukraine to win this war,” she said.

Europe’s relationship with Washington is also on Monday’s agenda, including how to cope with Mr. Trump’s demands. Officials expect the discussion to address his insistence that he wants to acquire Greenland. The island is an autonomous territory of Denmark, both an E.U. member state and a NATO ally. Danish and Greenlandic leaders say the territory is not for sale and will not be handed over to the United States.

The Greenland issue underscores just how drastically Washington’s relationship to Europe may be changing, as Mr. Trump seems more willing to put economic and military pressure on U.S. allies than on its adversaries.

But there is still a degree of shock in Europe.

“Nobody takes it seriously, or literally,” said Jacob Funk Kirkegaard, a senior fellow at Bruegel, a think tank in Brussels, who studies European economies and trans-Atlantic relations. “Nobody wants to do so, because it would require rethinking the world as we know it.”

While leaders like Mr. Rutte have emphasized that the continent cannot realistically go it alone without the United States, the goal is to be more self-sufficient.

E.U. nations have increased military outlays in recent years. They spent an estimated $340 billion on defense in 2024, a 30 percent increase compared with 2021. At least 23 of NATO’s 32 members now spend 2 percent or more of their gross domestic product on defense, in line with NATO goals. Mr. Rutte has made it clear that 2 percent is a floor, not a ceiling, and that a new, higher standard will be set this year.

With President Vladimir V. Putin of Russia busy with Ukraine and his military battered, European and NATO officials believe there is a window of perhaps three to seven years before Mr. Putin might be tempted to test the NATO alliance.

Finding a fix that boosts and coordinates European defense outlays will not be easy.

“The logic tells us that you need to have joint procurement,” said Janis Emmanouilidis, director of studies at the European Policy Center. But there are barriers, including a lack of trust between nations and conflicting national self-interest. “It is protecting national industry, it is protecting the sovereign right to make decisions,” he said.

When it comes to joint procurement, there is also the issue of how to finance it. Joint funding programs are clearly on the agenda, but exactly what that could look like varies.

It could mean a collective pot of money like Europe raised during the 2020 coronavirus pandemic. Funding could also come from a vehicle supported by the European Investment Bank, which is the lending arm of the European Union, or from a group of nations outside the structures of the bloc.

In a joint letter last week, 19 European countries said the bank “should continue exploring further ways to take an even stronger role in providing investment funding and leveraging private funding for the security and defense sector.”

The letter suggested a serious discussion of “specific and earmarked debt issuance” for defense projects. For now, key member states like Germany and the Netherlands reject the idea of collective borrowing for defense, and the EIB is prohibited from making loans for strictly military uses.

Any serious European defense would have to include Britain, a nuclear power and member of the United Nations Security Council, the main reason Mr. Starmer has been invited to attend. He has himself emphasized security cooperation with the European Union as a way to bring post-Brexit Britain closer to the bloc.

Mark Landler contributed reporting from London.