For decades, the United States has sat at the center of NATO, leading and managing, and occasionally micromanaging, Europe’s defense. NATO’s supreme allied commander is always an American, and NATO’s ultimate security guarantee is the U.S. nuclear deterrent. When Europe fights, it relies on U.S. aircraft and U.S. military transport and intelligence. If a NATO country were attacked, U.S. forces would take the combat lead. In NATO’s early days, as Europe rebuilt after World War II, the United States played this role out of necessity. But Washington became accustomed to calling the shots, and European leaders largely accepted a secondary role. Europe’s dependence on the United States has become a feature, not a bug, of NATO’s operations.


When NATO leaders meet at a summit in Washington this summer, the alliance’s 75th birthday should be cause for celebration. NATO is stronger than ever, having welcomed two new members, Finland and Sweden, within the past year. After decades of drift, the alliance has found new purpose in deterring Russian aggression, its original raison d’etre. At last, European countries are ramping up their defense spending. Together, these trends paint a bright future for NATO—but there is also peril ahead.

The effort to repel Russia’s invasion of Ukraine is stuttering, and a revisionist Putin is threatening its European neighbors. This, however, is not NATO’s fundamental problem. NATO knows how to deter Russia. The main problem, the one that makes solving the others more difficult, lies with NATO’s overdependence on the United States.

For decades, the United States has sat at the center of NATO, leading and managing, and occasionally micromanaging, Europe’s defense. NATO’s supreme allied commander is always an American, and NATO’s ultimate security guarantee is the U.S. nuclear deterrent. When Europe fights, it relies on U.S. aircraft and U.S. military transport and intelligence. If a NATO country were attacked, U.S. forces would take the combat lead. In NATO’s early days, as Europe rebuilt after World War II, the United States played this role out of necessity. But Washington became accustomed to calling the shots, and European leaders largely accepted a secondary role. Europe’s dependence on the United States has become a feature, not a bug, of NATO’s operations.

But now, with the rise of China and the beginning of a generational shift in leadership in Washington, the United States is unlikely to provide the level of support that Europe needs. No matter who sits in the White House, U.S. engagement with NATO is almost certain to weaken in the coming years.

Consensus is emerging on both sides of the Atlantic that Europeans must take charge of their own security—an attitude that has solidified in Europe since former U.S. President Donald Trump declared in February that Washington should not come to the defense of NATO allies that “don’t pay up.” But many American and European leaders have mistakenly concluded that all it will take to replace the United States’ contribution is to spend a lot more on security. In fact, even if all European NATO members were to meet the alliance’s goal of contributing two percent of GDP toward defense, their efforts would not significantly reduce Europe’s military dependence on Washington.

Europe does not just have a spending problem; it has a collective action problem. European countries treat defense policy as a national responsibility. Because most individual countries face few direct security threats, their governments, quite rationally, invest little in defense. Yet Europe as a whole does require protection from the grave threat of a revanchist Russia, and it must address the security risks that stem from a volatile periphery stretching from the Sahel to the South Caucasus.

Given how deeply the United States, through NATO, is involved in Europe’s defense system, no quick fix can ensure Europe’s security if the United States were to pull back. But it is still possible for Europe to shore up its defense. European countries will need to integrate their efforts, a process that will be difficult and slow and will require greater coordination both within the European Union and between the EU and NATO. Policy leaders should use the upcoming NATO summit to introduce a new strategy, one that will ensure that Europe has not only the equipment and personnel but also the organizational capacity it needs to stand and fight when confronted with a threat, with or without the support of the United States. Far from undermining NATO, this is an opportunity to make the alliance stronger and European countries more secure—as long as the United States gives Europe the time it needs to transform.


The United States has long stood in the way of Europe claiming a larger security role. The end of the Cold War brought opportunities to both reassess NATO’s direction and remake Europe, and ambitious plans for European defense were circulating inside the newly formed EU. In 1998, France and the United Kingdom reached what seemed like a historic breakthrough in the Saint-Malo declaration, which included an agreement for the EU to build an army of 60,000 troops. But Washington balked at the plan. Days after the declaration was announced, Secretary of State Madeleine Albright outlined a new U.S. position, known as “the three Ds”: any EU defense policy should not decouple European defense from the NATO structure, duplicate NATO capabilities, or discriminate against non-EU members of NATO. The United States made clear it would maintain its central role in European security, and its decision to box out the EU would stunt European defense integration in the decades that followed.

Resistance to changing this dynamic at NATO is still prevalent in Washington, at NATO headquarters in Brussels, and in many European capitals. The current bargain, after all, has served both Europe and the United States well for decades. By locking European countries into an alliance and guaranteeing their protection, NATO removed the security problems that once plagued the continent, and paved the way for the economic and political integration of Europe—a truly extraordinary achievement.

In exchange for the United States providing security for Europe, European capitals largely support American objectives elsewhere in the world. The U.S. military has been able to rely on built-in European coalitions during the wars in Afghanistan and even Iraq, as well as in more recent joint U.S.-European efforts to secure the Red Sea. European governments dutifully buy American weapons and are accustomed to having to make concessions on thorny policy issues, such as export controls on technology sales to China. With NATO alleviating the need for heavy investment in defense, European countries have also enjoyed the rewards of greater investment in social programs.

If Trump wins in November, NATO will be in grave peril.

Policymakers who work at or with NATO understandably have deep affection for the alliance as it is and are averse to altering the status quo. They want to believe that the U.S. commitment to NATO will not change. Many in Europe hope that by meeting Trump’s ransom demands—by spending two percent of GDP on defense and buying U.S. arms—they can also buy Washington’s perpetual support. They could be proved right, but sticking to this approach is an increasingly dangerous gamble.

If Trump wins the U.S. presidential election in November, NATO will be in grave peril. Trump sees NATO as a protection racket rather than as an institution that benefits the United States. And unlike his first administration, his second would likely include high-level officials who share the president’s skepticism. Plans are already circulating within Trump-aligned think tanks, such as the Center for Renewing America and the Heritage Foundation, that outline a significant U.S. retreat from NATO, including shrinking the size of NATO staff and pulling U.S. forces out of Europe.

Regardless of the U.S. election outcome, however, Trump has already broken the traditional bipartisan consensus in favor of NATO. Misgivings about the alliance are now widespread. Jamie Dimon, the CEO of JPMorgan Chase, remarked at this year’s Davos summit that Trump “was kind of right about NATO.” And Republican politicians are divided over the United States’ obligations to contribute to Europe’s defense. Senate Minority Leader Mitch McConnell, who supports a more traditional U.S. security role, has struggled to get younger Republican senators, such as Josh Hawley and J. D. Vance, on board with providing additional military aid to Ukraine.

Trump’s attacks on NATO also tap into a deeper American dissatisfaction with European military dependence that reflects a fading Cold War–era attachment to European security. When Americans travel to Europe, they see sophisticated infrastructure and citizens who enjoy high standards of living and robust social safety nets, and they cannot understand why their tax dollars and soldiers are needed to defend a well-off continent whose total population far outstrips that of the United States. Bipartisan disparagement of NATO allies’ low defense spending has also tarnished the alliance’s image. And even when European armies fight alongside the U.S. military, their comparatively small contributions earn them little praise. U.S. troops joked that the acronym for NATO’s ISAF operations in Afghanistan stood for “I saw Americans fight.”

The United States can no longer guarantee that its military will be able to come to Europe’s defense.

Most policymakers in Washington today have forged their careers in a post-9/11 world in which conflict in Europe seems less relevant. Because European allies brought so little to the table militarily, engaging them on issues such as security in the Middle East turned into a box-checking exercise condescendingly called “alliance management.” President Barack Obama, for instance, dutifully went through the diplomatic motions, but Europeans generally saw him as disinterested in European affairs. Even President Joe Biden, whose time on the Senate Foreign Relations Committee began during the Cold War and who maintains a deep attachment to NATO, seemed to treat Europe as an afterthought during his first year in office. His administration barely coordinated with Europe on the U.S. withdrawal from Afghanistan, and it signed the AUKUS submarine deal with Australia and the United Kingdom without considering the repercussions for U.S. relations with France, which felt blindsided when the deal superseded its own submarine agreement with Australia. The war in Ukraine drew U.S. attention back to Europe, but that attention is already beginning to wane.

Most important, the United States can no longer guarantee that its military will be able to come to Europe’s defense. Pentagon planners are laser-focused on a potential conflict with China, and should such a war break out, the United States would undoubtedly redeploy key capabilities, such as air defense systems and aircraft designed for transport and refueling, to the Indo-Pacific. Europe’s dependence on an overstretched U.S. defense industry would be a major vulnerability, as U.S. production would prioritize resupplying munitions and replacement equipment for U.S. forces in active combat. If the United States were to engage in hostilities with China, a revisionist Russia could also seize the opportunity to challenge NATO’s eastern flank. Deprived of the means to defend themselves, European countries could end up in the position Ukraine is in now, their war efforts undermined by a shortfall of U.S. supplies. That NATO is not already planning frantically for this scenario and European countries are not ramping up production and preparing to backfill systems that could be sent to the Indo-Pacific reveals that both are in a state of denial about where they rank on Washington’s list of priorities.


The EU and the United Kingdom together have a military force that is roughly two million strong. But it is a Potemkin force: its readiness and capabilities vary by country but are generally low, and separate national militaries cannot coalesce into a unified fighting force without the direction and material support of the United States. If Europe is to truly take responsibility for its own security, it needs to integrate its defense efforts.

This is a task for NATO and the EU to share. NATO would continue to act as Europe’s combatant command, in charge of military planning and warfighting, as well as providing a political-military forum for Europe to coordinate with the United States, Canada, and Turkey. NATO planners should draw up a blueprint showing how European forces can acquire the capabilities they will need to reduce their dependence on the United States.

The EU, meanwhile, should act as NATO’s investment and procurement arm, using its ability to mobilize resources on behalf of Europe. Where NATO sets standards and procurement targets, the EU would provide the resources. The EU should develop its own defense budget, funded by some combination of joint EU borrowing, member state contributions, or increasing revenue sources through tariffs, pan-European taxation, or other means. Member states would still be responsible for developing their own military forces, but the EU could take the lead in procuring expensive aircraft fleets or building a common stockpile of munitions. The EU can also integrate national bureaucracies’ efforts to strengthen Europe’s fledgling defense industrial base. It would not be duplicating NATO’s functions, because NATO has never brought European members together in this way.

A more integrated European defense is overwhelmingly popular among Europeans.

Euroskeptic defense analysts often dismiss proposals to integrate European defense as foolhardy efforts to create a European army. But this assessment misconstrues how European integration would work. The first stage would address tangible problems and gaps, such as making up for munitions shortfalls, which requires significant but straightforward investments. Only later would knottier defense integration issues that entail structural reforms—such as whether Europe needs its own nuclear deterrent and, if the answer is yes, who would control it—be put on the table.

Some analysts fear that expanding the EU’s security role would invite a populist backlash. But polling consistently shows that a more integrated European defense is overwhelmingly popular among Europeans. A recent pan-European survey by Bertelsmann Stiftung, a German research institute, found that 87 percent of Europeans support a common EU defense policy. Scholars have found that this strong support has been remarkably stable over time, and there is no reason to think that people’s attitudes would change when they learn the details of European defense integration plans. Another study, conducted in five European countries by scholars at the University of Amsterdam, found that EU citizens favor big ideas on European defense, including those that transfer responsibilities for military expenditure and even fielding troops from national governments to the EU, over less ambitious projects.

European politicians thus enjoy a generally permissive environment for advancing transformative policies. Some of them are recognizing the opportunity: ahead of EU parliamentary elections in June, leaders of the center-right European People’s Party, the largest party in the European Parliament and the one to which European Commission President Ursula von der Leyen belongs, have called for a dedicated EU defense budget of 0.5 percent of the bloc’s total GDP, on top of national defense spending.

European countries’ bureaucracies, not their publics, represent the biggest challenge. Today, 30 European defense ministries each bring their own vested bureaucratic and industrial interests to NATO. The ministries contribute to Europe’s shocking inefficiency in defense by applying idiosyncratic requirements, which often favor national defense companies, to weapons purchases. In practice, it makes little sense for each country to have its own processes. Most European defense forces, realistically, would be used only when NATO members act collectively. Yet European countries field a hodgepodge of equipment that makes it difficult for their militaries to deploy and fight together. For instance, after Russia’s invasion, both the Czech Republic and Slovakia bought armored vehicles from Sweden to replace the old Soviet systems they sent to Ukraine. But they ended up outfitting their vehicles with different caliber guns. The new systems are thus not fully interchangeable—a problem that could easily have been avoided had the two countries chosen to coordinate their procurement.


The EU has been able to integrate entrenched, protected state sectors before; successes such as its common agricultural policy provide proof of concept. Today, its work on the defense sector is already underway. Von der Leyen, who is running for a second five-year term as European Commission president this year, has proposed creating a new EU position, commissioner for defense, that would manage the EU’s expanding portfolio of defense initiatives and represent the EU both to member states and to third parties. The EU also has a new defense industrial strategy that encourages member states to buy the same defense systems—to address the interoperability problem—but its efforts need money to succeed. Estonia has proposed a scheme to create a 100-billion-euro fund for military aid to Ukraine and EU defense investment, which would serve as a starting point not just for further European support for Kyiv but also to expand the EU’s own defense activities.

Proper resources would allow the EU to procure and stockpile ammunition and buy new aircraft fleets—all without needing to formally change the Lisbon Treaty, which essentially serves as the union’s constitution. European NATO countries that are not members of the EU, such as Norway and the United Kingdom, could also be incorporated into EU efforts. Norway, by contributing to the EU budget, in some ways is already treated as a de facto member. The United Kingdom is a critical part of the European defense industrial base and its military forces are central to European security. The Labour Party, which is favored in the next British elections, has indicated its intention to bolster defense ties with the EU. Defense industrial cooperation could also help entice Turkey to stop blocking EU-NATO engagement because of its long-standing dispute with Cyprus (an EU member), which for years has impeded even basic coordination between the two institutions.

Integration does not mean replacing national defense forces with a single European army. France and Poland, for instance, will keep their own armies, but those armies should be able to operate together seamlessly, drawing on EU-funded forces and equipment.

Yet Europe may not have the time to integrate gradually. An abrupt withdrawal of U.S. forces from NATO might compel Europe to take dramatic action, but it could also leave the continent exposed militarily if it happens before Europe has built the capacity to guarantee its security. The shock could throw the continent into disarray. It would force Europe to face the most difficult aspects of integration immediately. On the issue of a nuclear deterrent, for example, some European states might rush to build their own stockpiles or make bilateral deals with Russia, creating deep splits within the EU and enabling wider nuclear proliferation.

The best option is for NATO leaders to push for a greater European role when the alliance convenes in Washington this summer. The United States should use its influence to advocate for European integration, and it should throw its support behind the kinds of EU defense efforts that Washington has historically opposed. A stronger, less dependent Europe would meet the United States as a genuine partner, giving Washington new reason to commit to the relationship. NATO, after all, will be more valuable as an alliance between two military powers than it is as a team led by just one.