As Russia’s war in Ukraine enters its third year, Europe has performed far better than expected. For decades after World War II, it counted on the United States to be the ultimate guarantor of its security. The continent relied on Washington to guide NATO policy, provide nuclear deterrence, and forge consensus among European countries on controversial questions such as how to resolve the 2009–12 European debt crisis. Europe continued to take the U.S. security umbrella for granted after the Cold War ended, slashing defense spending, failing to stop the Bosnian genocide in the early 1990s, and refusing to play a political role in resolving the crisis in Syria, even as it remained the region’s biggest provider of humanitarian aid. After Russia invaded Ukraine in 2022, many anticipated that Europeans might balk at helping Kyiv. The last time Russian President Vladimir Putin marched over Ukrainian borders—annexing Crimea in 2014—Europe responded with weak sanctions and halfhearted attempts at diplomatic compromise while increasing its dependence on Russian gas.

But over the last few years, the world has seen a glimpse of a stronger Europe. European countries have sustained a united front in resisting Russia’s aggression, hosting millions of refugees, coordinating painful decoupling from Russian gas supplies, imposing strong economic sanctions and export restrictions on Russia, training Ukrainian soldiers, and inviting Ukraine to join the European Union. The $53 billion EU aid package to Ukraine that was slated for approval in February set Europe’s combined economic and military assistance to Kyiv, including its multiyear commitments, at double the amount the United States is providing. For the first time since 2007, the EU has even gathered the confidence to substantially enlarge itself. In December 2023, it extended candidate status to Georgia and launched accession talks with Moldova and Ukraine.

These steps were undergirded by a solid transatlantic relationship. But European leaders cannot count on a friendly United States. They must prepare for the possibility that, a year from now, the United States will again be led by Donald Trump. During his GOP primary campaign for president, Trump has suggested that if he is reelected in November 2024, he will negotiate with Russian President Vladimir Putin to end the Ukraine war “in 24 hours,” demand that Europe reimburse the United States for ammunition used in Ukraine, withdraw from the Paris climate accords, and roil the global economy by imposing a ten percent tariff on all imports. 

Last December, the U.S. Senate passed a measure making it harder for Trump to unilaterally pull the United States out of NATO. But Europeans cannot depend on smooth military collaboration with a Trump administration: Trump directs special ire toward the alliance, and when he chooses his staff, he will likely pass over seasoned bureaucrats in favor of loyalists. Putin would likely interpret even the slightest hint that Trump may not fully honor the U.S. commitment to NATO’s Article 5 as an invitation to test the robustness of the transatlantic alliance, possibly even in the Baltic states.

Well before Russia invaded Ukraine, European leaders knew they had to grow up—which meant, in part, relying less on the United States. The European debt crisis motivated the EU to more fully integrate its banking systems. In some ways, the first Trump era spurred the EU toward greater self-reliance as Trump demonstrated that his only alliance was with his own interests. The EU established a European defense fund and a more constructive relationship with NATO. During the COVID-19 pandemic, European countries tasked the EU Commission with buying vaccines, and for the first time, the commission borrowed on a large scale to fund Europe’s economic recovery.

Only after Russia’s 2022 invasion of Ukraine, however, did the European debate—and behavior—about security change dramatically. Although Europe’s combined military and financial aid to Ukraine now exceeds that of the United States, U.S. support remains vital to Ukraine’s war effort—and to Europe’s broader security. And many longer-term consequences of Trump’s first presidency are still unfolding: peace around the world is unraveling, and authoritarian leaders are becoming bolder. Azerbaijan drove 120,000 Armenians from Nagorno-Karabakh unchecked. The rivalry between the United States and China has heated up. A chain of military coups in West Africa has ousted democratically elected presidents—as well as European peacekeepers. And thanks in part to policies instituted by Israeli Prime Minister Benjamin Netanyahu—whom Trump backed—a hot war has broken out in the Middle East. 

These are European problems, too. Refugees flooding to EU borders have an enormous impact on European domestic politics. Renewed conflict in the Middle East has prompted new waves of anti-Semitism and Islamophobia in Europe as well as a heightened threat of terrorism. Even if Ukraine thwarts Russia’s ambitions to rule its territory and people, Russia will likely remain a long-term security challenge, forcing Europeans to revisit collective defense scenarios and establish a level of military readiness it has not possessed since the Cold War. 

European leaders are hoping for a second Biden presidency that would protect the transatlantic bond and give them time and support to assume greater responsibility for their turbulent continent and neighborhood. But they may not get this time and support. A second Trump term may well exacerbate the instability Europe is already struggling to manage. Europeans will respect Americans’ choice of their next president. But it is in Europe’s hands to act now and take concrete steps to bulwark its security and economy. It must also increase the EU’s power, addressing institutional weaknesses that limit the organization’s capacity to lead in a world characterized by geopolitical conflict. In short, it needs to Trump-proof its future. The continent weathered four years of a Trump presidency. But a second four years will likely be much harder to sail through.

THE USES OF ADVERSITY

Trump’s first four years in power forced European policymakers to plan around a far less consistent and engaged U.S. president, one who took a distinctively transactional view of the transatlantic relationship. European leaders have traditionally had more in common with Democratic than Republican U.S. presidents, and the transatlantic relationship took strain long before Trump took office: think of the deep rift over President George W. Bush’s war in Iraq. 

But the challenges Trump posed were new. He was the first U.S. president who did not treat Europe as family. He seemed visibly more at ease with authoritarian rulers such as Putin and Chinese President Xi Jinping than with democratically elected European leaders such as German Chancellor Angela Merkel. Trump did not hesitate to withdraw from the 2015 Iran deal that President Barack Obama forged together with the EU and the E3—France, Germany, and the United Kingdom—nor to threaten to punish Europeans with sanctions if they abided by it. He also failed to consult with European leaders or even inform them before making major foreign policy moves, such as inking the 2020 Abraham Accords or withdrawing U.S. troops from Syria. Trump not only abandoned the United States’ plans for a trade deal with the EU. He instituted unprecedented protectionist measures that targeted European exporters.

And he sought to weaken multilateral cooperation in areas such as climate change, trade, migration, and human rights, withdrawing from the Paris climate accords—an EU priority. He undermined international organizations such as the World Health Organization and UNESCO, as well as the UN’s attempts to reach an agreement on handling migration and refugees. Trump’s actions had a galvanizing effect on Europe: the United States had played a star part in shaping the EU itself, but then the country seemed to withdraw from its lead role in supporting the rules-based international order.

Europe’s leaders realized their continent had to become more sovereign and autonomous—plainly put, more capable and responsible for world affairs. They had to step up to sustain the multilateral system. The EU, for example, increased its support for the World Health Organization. Trump’s threat to put economic sanctions on Europe sparked the continent’s leaders to strengthen the euro by further integrating their banks and financial systems and to sign trade agreements with new partners in Africa, Asia, and Latin America. In terms of security, Trump’s attacks on Europe’s low defense spending and his threats to leave NATO pushed the EU to take steps toward establishing institutional, legal, and financial incentives for European countries to spend more on defense. The European Peace Facility, an EU mechanism to provide military assistance to other countries—which the EU has used since 2022 to provide military aid to Ukraine—was created in response to the pressure Trump put on the continent.

But other phenomena that emerged in the Trump years proved more difficult to manage—most important, his rhetorical attacks on law and order and centrist democracy. When Trump pressured Ukraine, in 2020, to damage his Democratic rival’s candidacy, he legitimized the tactic for other actors. Populist forces in Europe read off Trump’s harsh script when it came to immigration, hobbling EU efforts to enact a general policy on migration. Overall, Trump actively supported right-wing nationalists, populists, and anti-EU voices in Europe. As the EU heads into parliamentary elections in June 2024, there is a real risk that these emboldened forces will gain significant ground, shaping the EU’s future generation of leaders. Whether they do or not, Trump’s second candidacy is already encouraging nationalist figures such as Hungarian Prime Minister Viktor Orban. 

DOUBLE TROUBLE

Trump may well be more antagonistic to Europe and European values in a second term, dramatically increasing the risks to the continent’s security and aggravating its existing difficulties. A reelected Trump would be completely unchained from the old, pro-democracy Republican establishment. He would likely surround himself with loyal administrators who do not challenge him. Moreover, the world has grown accustomed to his outrageous statements and decisions, making individual transgressions feel less shocking and less crucial to resist.

The biggest immediate danger presented by a second Trump term is clear: Trump has already indicated he would end U.S. support for Ukraine. Although Europeans have been increasing their financial and military support to Kyiv, both bilaterally and using the EU’s toolbox, their efforts fall short of fully substituting for U.S. military assistance. In fact, the EU’s short-term military support to Ukraine constitutes only 55 percent of what the United States has offered. A scenario in which the United States completely terminates its assistance to Ukraine is not in the realm of fantasy, and it would require Europeans to more quickly and comprehensively support Ukraine.

The critical issue for the Europeans to understand is that the risk posed by a more isolationist United States goes beyond Europe’s eastern border. For decades, Europeans have tolerated significant shortfalls in their defense budgets and capabilities. This explains European countries’ limited capacity to ramp up defense industrial production to arm Ukraine and replenish stocks of ammunition and weaponry. Europeans reasonably assumed that the United States would take the lead in an emergency.

The essential contribution the United States makes to European security is no longer primarily boots (and tanks) on the ground, as it was during the Cold War, but in domains such as intelligence, reconnaissance and surveillance, strategic air transport, air-to-air refueling, and space observation and communication. It also offers comfort in the form of nuclear deterrence and the ability to quickly deploy a significant volume of highly trained forces if needed. In practice, the United States is currently the only NATO ally that has a truly “full force” package.

The risks a second Trump presidency poses, however, go well beyond defense and security. Under Trump, the U.S.-Chinese relationship could further deteriorate. This would put European firms that operate in both jurisdictions in a difficult position: by threatening secondary sanctions, Trump could actively force European companies to cease operations in China or pressure Europeans to block Chinese investments in Europe. Trump has promised to impose a ten percent tariff on all imports if he is reelected, and the impact of such a move—were Congress to approve it—would be acutely felt in Europe. Europe could also see its digital sovereignty affected by the reelected U.S. president. For capabilities including geolocation, satellite-based communication, cloud computing, data privacy, and AI, Europe is dependent on the United States and vulnerable to disruption.

For decades, the deepening of democracy in Europe has been tied to U.S. influence. As recently as 2021, the Biden administration stepped up to defend freedom of the press in Poland by convincing the Polish president to veto a controversial media bill that would restrict who could own local broadcasters. If he gets a second term, Trump may well seek to further weaken democratic institutions in the United States, including the Department of Justice, and foment general disdain for the rule of law. This would embolden populists and Euroskeptic parties. The first Trump presidency already taught Europeans how a U.S. president’s political support for populists can practically endanger European unity. 

THE BEST OFFENSE

Europeans want to preserve the cherished transatlantic relationship. But they need to urgently prepare for a weakened one. First, Europeans must more categorically shift their attitude toward Europe’s defense. In the immediate term, European leaders must ramp up the production and procurement of materiel to support Ukraine: Kyiv needs an estimated two million rounds of ammunition or more per year, as well as replacement artillery barrels, spare parts, and air defense systems. Europe must immediately decide whether to expand its ability to produce ammunition and other critical weapons. Some of the world’s foremost armament producers are European, and boosting their capabilities is practically and financially within reach, but it will require much more deliberate planning. 

Even if Ukraine did not have such acute immediate requirements, Europe would need to increase its weapons and ammunition production, because European armies need to reconstitute their defense supplies and address shortfalls. The speed with which European countries have deployed troops to NATO’s eastern flank since 2022 has been impressive. But to ensure those forces’ long-term effectiveness, Europeans must improve their training and logistics planning. The continent must also build up its fleet of critical strategic enablers, such as drones and satellites, and develop its cyber and airlift capabilities.

This strategy will benefit from a concrete plan similar to the one the European Commission created to successfully fast-track the development and production of COVID-19 vaccines. Currently, European countries’ budget forecasts and planning cycles often fail to offer weapons manufacturers the assurances they need to increase production. In 2022, for example, Germany established an impressive $110 billion five-year emergency fund to rebuild its armed forces. In 2023, however, the German defense minister admitted that this will not be enough money.

In 2022, European countries—both EU member states and NATO allies—spent a total of $350 billion on defense. A sustained effort by these countries to spend a minimum of two percent of their GDP on defense, or about $450 billion per year, would significantly reduce Europe’s dependence on the United States. The EU must play a stronger role as an accelerator and facilitator, using financial incentives and regulatory measures to mobilize member states and discourage unnecessary duplication of effort. Even if most defense spending remains national, the EU can use its budgetary resources for defense research and technology and to strengthen manufacturing capacity by placing joint orders to defense companies through the European Defense Agency or other collective mechanisms. It can employ the European Investment Bank and other financial tools to support this defense effort, as well as relax some fiscal and deficit constraints to favor defense investment.

All these goals require Europe to plan ahead because building defense capability takes time. Waiting to move until the U.S. election has been decided is not an option. The EU will not be able to quickly acquire the same skill in planning and commanding large-scale territorial defense operations that NATO has developed over 75 years. But Europeans can Europeanize the NATO command structure by deploying manpower and investing resources to cover for a U.S. retreat from the organization. A more European NATO might be able to adequately compensate a reduced American commitment even if the alliance loses some transatlantic backing. It would also address Trump’s recurring criticism that the United States shoulders too big a share of NATO’s tasks. And should the United States soften its commitment to provide nuclear deterrence to Europe, France and the United Kingdom—Europe’s two nuclear powers—must revisit their contribution to deterrence. All Europeans, too, will need to discuss effective policies that could prevent nuclear escalation.

RISKY BUSINESS

Because Europe is such an open economy and transatlantic trade relations run so deep, a more hostile United States can badly damage Europe. For now, the EU has no appropriate institutional framework to react to economic security risks from China—or from a more hostile United States. Economic security is mostly handled by member states, not the EU itself, and incongruent security policies on imports, exports, investments, and financial flows pose a growing threat to the European economy.

Consider digital security: the consequences of a second Trump presidency could be particularly severe in the digital space unless Europe acts now. European countries manufacture relatively little of their own cloud-computing systems, key software, and telecommunications infrastructure. They depend on both American and Chinese products. But when a European telecom operator active in several countries incorporates Chinese equipment into its infrastructure, security risks can easily spill over borders. 

In the event of heightened political confrontation between China and the United States, Trump could threaten sanctions on major telecom operators who use Chinese equipment. The EU must have a ready, forceful response teed up or the EU telecommunications market could fragment. European countries must also work to reduce their dependence on Chinese telecommunications products to prepare for a tougher line from the White House.

Europe currently sources the lion’s share of its cloud-computing capacity—essential to military operations—from the United States. If Trump is reelected, he is likely to undo recent transatlantic efforts to cooperate on data privacy. To ensure legal immunity from foreign laws, EU countries may want to follow the examples of France, Italy, and Spain in demanding that cloud-computing services be exclusively provided by firms whose headquarters and staff are located in the EU. Even before the U.S. election, the EU can move to secure cooperation with the United States on digital matters; it is important to show the country’s leaders that such transatlantic cooperation also benefits the United States. European leaders, for instance, could already begin cooperating more closely with Washington on AI governance, setting standards that limit harmful applications of AI technologies.

China is increasingly investing in European strategic infrastructure, illuminating the problem of having an integrated market without properly integrated security. In 2016, the Netherlands allowed major Chinese investments into the Rotterdam port, and in 2023, the China Ocean Shipping Company took a share in the port of Hamburg. But the EU could not formally weigh in on either the Dutch or the German decision, even though goods arriving in Rotterdam are not primarily destined for the Dutch market but make their way throughout the entire EU.

The EU, as an institution, is also weak on export restrictions and sanctions policy. The exporting of dual-use high-tech goods is often limited by individual countries, sometimes under pressure from the United States. The Dutch government’s recent decision, for instance, to limit the export of Dutch lithography machines needed to produce top-performing semiconductor chips affected the entire EU. It required Zeiss, a German company, to ensure that the components it supplies for those machines are not instead delivered directly to China, undermining the Netherlands’ export restriction, and the German government has even been debating whether German engineers who know how to develop these machines should be banned from working in China. As for sanctions, the EU has been able to pass 12 sanctions packages against Russia. But unanimity requirements make decisions slow, and enforcement remains imperfect.

Because Trump favors bilateral relations over working with the EU, it is EU oversight of economic security that must be improved, lest individual countries diverge even further on their policies. The EU needs to commit to institutional reforms—for instance, moving from requiring a unanimous vote to approve some economic-security policies to allowing their adoption with majority votes. It should also establish an economic security committee, staffed by economists and security experts from EU institutions, as well as member states, to undertake security assessments of decisions that affect the whole EU.

Protectionist policies instituted by Trump would damage the world, but they could particularly harm the EU. Europe must become more economically competitive by forging trade agreements with third markets—especially given the U.S. reluctance to define its trade policy—and deepening its single market. The EU has not sufficiently integrated its single market, particularly the financial, digital, and service sectors. More integrated banking and capital markets would provide businesses with much-needed funding and would support entrepreneurs, who too often leave the EU to get access to U.S. venture capital. Furthering the EU’s economic integration has a political purpose, too. To counter the rise of populism in countries such as France, Germany, Italy, the Netherlands, and Spain, the EU must show that more economic integration can help ordinary citizens.

LANGUAGE LESSONS

Perhaps the greatest risk Trump poses to Europe is to its values: multilateralism, care for the environment, the rule of law, and democracy itself. Through his rhetoric, Trump degrades the worth of these principles in public opinion. Europe needs to start preparing now to withstand that pressure internally, girding itself to better defend the rule of law within its borders. A potentially powerful EU instrument to protect the rule of law has existed since the 1999 Treaty of Amsterdam: a procedure outlined in Article 7 of the EU treaty that allows member states to sanction a country when it commits “a serious and persistent breach” of European values. In effect, however, this instrument has often been toothless, because other EU states must agree unanimously that a member state undermined the rule of law.

To get around this unanimity requirement, in 2021 the EU adopted a regulation allowing the European Commission to suspend certain payments from its budget if only a qualified majority of EU states found that a member state had breached EU values. The effectiveness of this regulation is currently being tested: the EU is now withholding, for instance, some COVID-19 recovery funds from Hungary after finding that the country had persistently breached the rule of law. But if the EU is serious about defending its principles, it should not shy away from considering the use of treaty provisions that suspend a member state’s voting rights in the European Council.

The EU must also promote democracy in its direct neighborhood by using the most effective tool it has: EU enlargement. Previous rounds of expansion have shown that the EU accession process itself gives the body considerable leverage to transform the governance and political culture of applicant countries. Russia’s war of aggression against Ukraine has given the accession process new meaning and urgency. The EU should aim for another major big bang enlargement round by 2030: setting a concrete date for such an expansion would motivate some applicant countries to undertake reforms and strengthen their democracies with a view toward fulfilling the conditions to enter the EU.

Worldwide, Europe must become more outspoken and determined in defending democracy, the rule of law, and multilateralism. Europe is already a keystone to global efforts to protect the climate and defend against threats to public health; ahead of a potential Trump reelection, it needs to work hard to keep its global partners rallied behind those goals. The EU should also use its existing partnerships with advanced and developing economies more strategically. The EU’s Global Gateway Initiative could serve as the backbone for deeper trade, investment, and financial partnerships with developing countries that support international cooperation in a world characterized by U.S. isolationism and growing geopolitical rivalry. Many developing countries have long looked to the United States as an example of the dividends that democracy pays. They have also depended on Washington for material support. European leaders must step up so the world can also look to Europe.

Even if Trump does not win in November, Europe has work to do. It may simply no longer be able to rely on the United States to be a consistent partner, no matter who’s in charge. The United States is already making foreign policy moves without consulting Europe, especially in the economic sphere. President Joe Biden’s 2022 Inflation Reduction Act, for instance, was also an act of protectionism. Using subsidies and domestic production requirements, it induced European firms to relocate to the United States at a cost to Europe’s economy. Both Republican and Democratic lawmakers have made it clear that they intend to prioritize the Indo-Pacific going forward, and circumstances may draw U.S. military efforts toward the Middle East and Asia. The partisanship that roils the U.S. Congress will likely become an increasingly difficult obstacle to a flourishing transatlantic relationship. And the worrying state of America’s democracy at home is likely to absorb more political energy than European priorities such as battling climate change.

Europe handled aspects of Trump’s first presidency surprisingly well. But it needs to grow more as wars flare and climate change accelerates. Surveys regularly show that European citizens want the EU to play a larger role in solving global challenges. In 2024, EU leaders must heed their desires by making bold, concrete moves to boost European defense, secure their countries’ economic sovereignty, and protect democratic values.

Should Trump be reelected, the risks to Europe’s unity will be substantial. Some European leaders may feel tempted to forge bilateral deals with the United States to try to guarantee their country’s security in the short term. But Europeans need to remember that Trump cannot be relied on—and that the United States cannot guarantee Europe’s security forever. Instead of gambling on national self-reliance, they should bet on a more integrated Europe.

The European Parliament election in June presents an opportunity. A business-as-usual election campaign would not do justice to the challenges that may lie ahead. Instead, political parties need to debate fundamental strategic choices and make the defense of democracy and EU institutional reform a key part of their appeals. The message the EU sends in its election campaign must be a strong counterpoint to an isolationist, antidemocratic rhetoric: Europe will be able to protect its own borders, defend human rights, help safeguard open trade, fight climate change, and champion democracy, even if the United States won’t. And the United States may, in fact, be able to look to Europe for help and inspiration if it stumbles.