The first time Donald Trump was president he almost quit NATO; now that he’s back in office he’s more unpredictable than ever.
Allies meeting in The Hague this week are already worried the U.S. president is abandoning Ukraine. They’re expected to agree to a massive defense spending boost to placate him and make sure he doesn’t also leave Europe alone against Russia.
Europe’s problem is that there is no obvious country, or even grouping of countries like the U.K., France, Germany and Poland, that could truly compensate for a lesser American involvement. And the European countries each face massive fiscal, military and political challenges.
“The advantage of American leadership is that it was so superior, massive and benevolent that no one could dispute it: It brought order to the playground, there was no question of who decided,” said a high-ranking French military officer.
In a situation where Washington isn’t the driving force behind either NATO or European security, “there would no longer be a true alpha male,” the officer added. “No one else can assert its predominance by force.”
L’Observatoire de l’Europe and WELT, a sister publication of L’Observatoire de l’Europe in the Axel Springer Group, spoke to more than a dozen current and former European and American policymakers, military officers and academics about what NATO and European security would look like with a lesser role for America.
While all insisted that the U.S. is unlikely to actually pull out of NATO, there’s a broad agreement that the military alliance is going to have to change — and that could push other countries into taking on more of a leadership role.
In the meantime, allied leaders will be tiptoeing around Trump in The Hague to ensure he leaves happy.
“Instead of hoping that the U.S. would remain in Europe and confirm its pledge to mutual defense, which might happen, we have to think about how it would work if, for one reason or another, the U.S. is not there or not in the way that we expected it to be,” warned Lithuania’s former Foreign Minister Gabrielius Landsbergis.
Europeans have relied on the U.S. for decades. Washington’s conventional and nuclear weapons have provided essential security in a transatlantic alliance based on common military, economic, political and cultural ties.
All of those are now fraying, forcing Europe to ask itself some hard questions.
Trump’s behavior, from tying American security guarantees to how much a country spends on defense, to praising Russian President Vladimir Putin while publicly humiliating Ukraine’s Volodymyr Zelenskyy and threatening to invade Greenland, a Danish territory, and annex NATO ally Canada, is sapping that decades-old confidence.
In parallel, the U.S. administration is conducting a review to assess whether some U.S. troops stationed in Europe will be redeployed elsewhere, even as fears grow that Putin could attack NATO territory in the next five years.
“If Moscow decides to attack a NATO country, we don’t really know if Trump will go to war against Russia. Before, under the Biden administration, we were sure that the U.S. would. We were banking on the deterrent effect; we were banking on the fact that Russia wouldn’t even try,” said Barbara Kunz, director of the Stockholm International Peace Research Institute’s European security program.
Washington insists that it’s sticking with NATO, but change is coming.
U.S. ambassador to NATO, Matthew Whitaker, said Washington would start discussions about U.S. troop reductions with allies after the NATO summit. He also said the U.S. is committed to NATO’s common defense Article 5 — as long as allies pour enough cash into their militaries.
In a lot of European capitals, there is a reluctance to engage with the idea that the U.S. might not be a reliable ally.
“It’s an uncomfortable topic to many,” Landsbergis said. “I’m kind of privileged to have the opportunity to speak about this, because I’m more free now than when I was a minister. Many think that if you start talking about this, you weaken NATO.”
The closer to Russia, the stronger the insistence that America and its soldiers, tanks, warplanes, missiles, heavy lift capacity and nuclear weapons are not going away.
“I can confirm that the Americans are fulfilling their obligations within NATO. Our exchange, our cooperation is very good,” said Paweł Zalewski, Poland’s deputy defense minister. “Trump’s rhetoric aims to persuade Europeans to invest more in the defense of their own continent. That is working, and we are happy with it in Poland.”
Many Europeans also hope that Trump will blow over and transatlantic relations will return to the familiar pattern of past decades.
“There is disagreement among Europeans about the scale and duration of the problem,” said SIPRI’s Kunz. “There are still some who think there’s no point in thinking about a plan B right away because we’ll be able to either return to normal in 2028 with a good guy back in the White House or make deals with Trump.”
There are many reasons why capitals do not want to contemplate a future with less American involvement in Europe’s security. Even talking about it publicly could project an image of weakness toward Putin, officials argue.
One of the reasons is how daunting replacing U.S. military equipment and support is. A study by the International Institute for Strategic Studies published last month found that the costs of like-for-like replacement of U.S. weapons and its 128,000 soldiers would add up to approximately $1 trillion over 25 years. The most pressing dependencies are critical enablers, namely satellites, deep-strike capabilities, air-to-air refueling and tactical transport.
« Our aim is not to replace the U.S. within NATO, but to complement it with more European capabilities. Some U.S. capabilities, such as a credible nuclear deterrent, could not be provided by Europeans for many years, » said Norbert Röttgen, a German Christian Democratic MP and a convinced transatlanticist.
The other reason for avoiding the issue is the fear of a self-fulfilling prophecy: If Europe steps up and shoulders most of the burden of defending the continent, that could also be a pretext for the U.S. to reduce its involvement in NATO even more — which most Europeans do not want.
When it comes to « the U.S. potentially leaving Europe, we should do nothing on our side that would accelerate this development, » said former German Foreign Minister Joschka Fischer.
Besides frontline countries such as Poland and Lithuania, the U.K. has also been particularly strict about shutting down any talk of divergence between its own strategic interests and those of the U.S.
In public and in private, British ministers and officials maintain that the U.S. remains completely committed to NATO while acknowledging the need for European countries to take on more responsibility for their own defense. One British member of parliament with a background in defense spoke of the need to handle America “carefully.”
However, several former and current European officials warned that Europeans should work on every possible scenario.
« We must prepare by thinking on two tracks: one with America, one with only Europe, » said Fischer.
Most discussions about NATO’s future acknowledge that replacing America would have to be a joint effort.
An early example of stepping in for a retreating America is the Ukraine Defense Contact Group — an informal gathering founded by the U.S. to coordinate military aid to Kyiv. Washington abandoned the leadership of the group under Trump, and it’s now headed by a tandem of Germany and the U.K.
Another one is the so-called coalition of the willing, spearheaded by London and Paris to provide Ukraine with security guarantees in case of a ceasefire.
That shows no European country alone can claim leadership on European security in the way that the United States has since the war.
« France, Britain, Germany, Poland — those will be the decisive factors, » said Fischer, echoing most of the people L’Observatoire de l’Europe and WELT spoke with. « The smaller Baltic and Scandinavian states will also have an important voice, » he added.
To make up for less American leadership, « we are typically in a coalition scenario,” according to Jean-Louis Thiériot, an MP and a former French deputy defense minister.
But it is crucial to go beyond the Weimar Triangle of Germany, France and Poland and broaden it to include the U.K., he said. “The problem with trios is that it always ends up being two pitted against one. »
Each of the four nations would bring assets to the table, the lawmaker explained: Paris and London are nuclear powers, Berlin is an economic heavyweight and Warsaw has an acute understanding of the Russian threat as well as Europe’s largest military (bar Turkey) and NATO’s highest defense budget as a percentage of gross domestic product.
But each country could also be a weak link.
It’s unclear whether France and the U.K. — the two countries which have shown the most willingness to embrace leadership roles — have the cash to spend on defense.
France’s public finances are dire and President Emmanuel Macron still hasn’t explained how his country will be able to increase defense spending. Besides, France’s full-scale commitment to NATO is fairly recent, and trust with frontline countries is still a work in progress.
British Prime Minister Keir Starmer has similar budgetary pressures, while also facing a credibility gap. “The issue has always been that we commit a lot to NATO, but we don’t really deliver it,” said Ed Arnold, a senior fellow at Britain’s Royal United Services Institute defense think tank, citing promises for a new land forces division in 2025 which has now been deferred to 2030.
Traditionally pro-American Poland could be a bridge to the Trump administration — but the recent victory of Karol Nawrocki, backed by the nationalist Law and Justice party, in the presidential election has weakened Prime Minister Donald Tusk. His government is likely to be in a permanent crisis until the parliamentary election in 2027 — and domestic paralysis is likely to translate into less weight in foreign policy.
Poland is also setting off alarm bells thanks to its fast-growing deficit fueled by increased defense spending.
As for Germany, there are doubts about Chancellor Friedrich Merz’s political will to take on a leadership role, despite grand statements on the campaign trail about the need for more autonomy from the U.S.
Rather than setting the agenda, Berlin remains dependent on the initiative of others — particularly London and Paris, said Carlo Masala, professor at the Bundeswehr University in Munich. “If Germany wants to lead, it just can’t follow Franco-British plans. It needs to come to the table with its own.”
Trump’s return to the White House shows that alliances, even if rooted in treaties, can be upended by an election.
That risk also applies to Europe.
The U.K. and Germany are both early in their electoral cycles — but nationalist, far-right parties that could work against European defense cooperation and don’t share the same Russia threat assessment as NATO allies are increasingly powerful in both countries as well as in France, which holds a high-stakes presidential election in less than two years.
“What could work today with Macron, Starmer and Merz might not work tomorrow with Marine Le Pen, Nigel Farage and Alice Weidel,” said the French military official mentioned earlier, referring to the leaders of populist, far-right parties in France, the U.K. and Germany. “How is it possible to build something with countries that could become tomorrow the opposite of what they are today?”
Gesine Weber, a research fellow at the German Marshall Fund of the United States, said: “Everyone agrees that this is now a window of opportunity (for cooperation), but the domestic political trajectory in the two nuclear powers does make other Europeans wonder about their future reliability.”
That shouldn’t prevent current European leaders from working together, she added.
“What is crucial for Europeans is not to fall into paralysis because they’re afraid future governments in France or the U.K. will be less committed to defense alliances. It’s crucial that they don’t commit suicide because they are afraid of death.”
