Foreign Affairs - The Allies After America In Search of Plan B - Philip H. Gordon and Mara Karlin - January/February 2026 - Published on December 16, 2025

 

Foreign Affairs

The Allies After America

In Search of Plan B

Philip H. Gordon and Mara Karlin

January/February 2026

Published on December 16, 2025

Mona Eing and Michael Meissner

The first year of the second Trump administration has demonstrated—if any more proof were needed—that the days when allies could rely on the United States to uphold world order are over. For the 80 years since the end of World War II, every American president, with the partial exception of Donald Trump during his first term, has been at least somewhat committed to defending a set of close allies, deterring aggression, supporting freedom of navigation and commerce, and upholding international institutions, rules, and laws. U.S. presidents were far from consistent in pursuing these goals, but they all accepted a basic premise that the world was a safer and better place, including for Americans, if the United States devoted significant resources to advancing these aims. Under the second Trump presidency, that is no longer the case.

Trump’s abandonment of traditional American foreign policy has profound implications for the evolving world order and for all countries that have relied so heavily on the United States for decades. Because the reality is that they have no obvious Plan B. Many of Washington’s closest friends are unprepared to deal with a world in which they can no longer count on the United States to help protect them, let alone one in which it becomes an adversary. They are reluctantly starting to recognize the degree to which the world is changing, and they know they need to prepare. But years of dependence, deep internal and regional divisions, and a preference for spending money on social needs over defense have left them without viable near-term options.

For now, most U.S. allies are simply playing for time, trying to preserve as much support from Washington as possible while they contemplate what comes next. They flatter Trump with obsequious praise, give him gifts, host him at lavish events, promise to spend more on defense, accept unbalanced trade deals, pledge (but do not necessarily make) massive investments in the United States, and insist that their alliances with the United States remain viable. And they do so in the hopes that, as after Trump’s first term, he may again be replaced by a president more committed to maintaining Washington’s traditional global role.

Their thinking, however, is wishful. Trump will be in office for three more years, which is more than enough time for the alliance system to degrade further or for adversaries to take advantage of the vacuum the United States has left. Those who believe in alliances, global rules, norms and institutions, and American self-interest in keeping up partnerships can hope that Trump’s approach will not be a lasting one and proceed accordingly. But that may be unwise. Trump represents American attitudes toward foreign policy as much as he shapes them. A generation of failed interventions abroad, growing budget deficits, accumulating debt, and a desire to focus on domestic affairs have left Americans across the political spectrum more reluctant to bear the burdens of global leadership than they have been since before World War II. U.S. allies may not have a Plan B now—but they had better start developing one fast.

PLAYING FOR TIME

In Trump’s first term, the United States’ commitment to supporting its network of global alliances bent but did not break. This was partly because Trump was new to the job, more cautious (in his actions, at least), and not quite ready to revolutionize U.S. foreign policy—but also because he staffed his administration mostly with proponents of traditional foreign and defense policy. His top foreign policy advisers all shared the belief that the United States should be active globally and that it benefits substantially from the political, security, and economic system that had been in place since the 1940s. Notwithstanding his “America first” platform and his own more radical instincts, Trump hesitated throughout most of his first term to take steps that would threaten U.S. global leadership. For example, he considered withdrawing American troops from Germany, Iraq, Japan, South Korea, and Syria but never did so—often because of pushback from his top advisers.

The second Trump administration is different. This time, the so-called globalists are out, and the president is surrounded by people who see most U.S. commitments abroad as a net burden. Vice President JD Vance, Secretary of Defense Pete Hegseth, and Director of National Intelligence Tulsi Gabbard all served in the U.S. military in Iraq and emerged from that experience with deep resentments of U.S. foreign policy elites and the United States’ overseas undertakings. When he was in the Senate, Marco Rubio, who is now serving as both national security adviser and secretary of state, was a strong proponent of standing up to Russia, defending human rights, and providing foreign assistance. Today, however, he appears to have suppressed those convictions to remain relevant and trusted by Trump and the MAGA base. Simply put, the current administration’s worldview appears to be far more influenced by Trump’s long-held beliefs: alliances are an unnecessary burden, autocracies are easier to deal with than democracies, an open trading system is unfair, the United States can sufficiently defend itself without help from other countries, and great powers should have the right to dominate their smaller neighbors—and even to acquire new territory when it is in their interest to do so. The postwar world, built around mostly democratic allies that rely on the United States for security and defense, is gone.

This line of thinking is most evident in the administration’s approach to Europe and NATO. Whereas past presidents expressed an ironclad commitment to NATO’s Article 5, which says that an armed attack on any one member will be considered an attack on all, Trump has suggested that the guarantee applies only if allies “pay their bills”—that is, contribute more to collective defense. And early in his second term, Trump expressed his intention to take control of Greenland, which is a territory of Denmark, a NATO ally. He even suggested the United States could do so by force, raising the prospect of the United States using its military not to protect a member of NATO but to attack one.

Americans are now more reluctant to bear the burdens of global leadership.

Vance is, if anything, even more skeptical about the traditional U.S. role in European security. In 2022, he said he didn’t “really care what happens to Ukraine one way or the other.” In February 2025, Vance told the audience at the Munich Security Conference that he worried more about threats “from within” Europe than those posed by China or Russia. Later that month, he said that Denmark was “not being a good ally” and suggested Trump might “take more territorial interest in Greenland” because he “doesn’t care about what the Europeans scream at us.” And in a Signal chat with top administration officials in March, Vance complained about “bailing Europe out again.”

U.S. policy in the first year of the administration has reflected these views. Trump has embraced Russian narratives about the causes of the war in Ukraine, provided no direct U.S. military assistance to Kyiv beyond what was already in the pipeline, and refused to offer Ukraine a meaningful security guarantee. When Russia launched drones into Poland in September 2025, Trump downplayed it as a possible mistake, and when Russia violated Romanian and Estonian airspace that same month, the United States largely sat out NATO’s military response. The Trump administration also announced that it would stop providing military assistance to countries on Russia’s border. In October, it began withdrawing some of the additional troops the Biden administration sent to help defend Europe after Russia’s invasion of Ukraine.

U.S. partners in Asia also have plenty to worry about. For over a decade, Washington touted its intention to “pivot to Asia,” but now it appears that the United States’ priority is its homeland and the rest of the Western Hemisphere. Trump’s first National Defense Strategy, published in 2018, focused on countering Russia and China. The Biden administration’s strategy considered China to be the United States’ “pacing challenge”—the primary threat against which the U.S. military should be scaled and shaped. But officials in Trump’s second administration seem to be questioning that priority and focusing instead on border security, counternarcotics, and national missile defense, along with greater burden sharing by U.S. allies.

Trump has broadly maintained the United States’ network of military partnerships in the Indo-Pacific, but allies there worry that he could subordinate support for their security interests to his desire for an improved relationship—and, possibly, a big trade deal—with China. In his first term, Trump conditioned U.S. security commitments to Japan and South Korea on their willingness to pay more for their own defense, even though the United States maintained defense treaties with both countries. Trump has also halted U.S. arms deliveries to and limited diplomatic interaction with Taiwan, declined Taiwan’s president permission to transit the United States en route to Latin America, and begun allowing China to buy more advanced semiconductors, apparently to create conditions for a successful relationship with Chinese President Xi Jinping.

A U.S.–South Korean exercise in Yeoju, South Korea, August 2025

Kim Hong-Ji / Reuters

Whereas U.S. President Joe Biden repeatedly said the United States would help defend Taiwan in the event of a Chinese invasion, Trump has remained noncommittal. And Commerce Secretary Howard Lutnick has gone so far as to suggest that the United States would protect Taiwan only if Taipei agreed to move half of its advanced chip-building capacity to the United States. It is not difficult to imagine Trump refusing to defend U.S. allies and partners in the Indo-Pacific in the event of conflict.

Trump also seems disinclined to expend American resources to maintain the U.S.-led order in the Middle East. To be sure, he has staunchly supported Israel, and in September issued an executive order granting Qatar a formal defense commitment. But Trump worries more about getting dragged into war than about defending U.S. partners, countering terrorism, preventing nuclear proliferation, and protecting national security interests. He clearly values his relationships with Gulf leaders, but that doesn’t mean he would defend them any more than he did in 2019, when he did nothing after Iran struck a major Saudi oil refinery and tankers off the coasts of Oman and the United Arab Emirates.

Trump has historically been willing to support allies with military force only when the risk of escalation, especially with great powers, was low. During the 12-day war between Israel and Iran in June, for example, Trump launched strikes against Iranian military and nuclear sites only after Israel had destroyed Iran’s air defenses and capacity to strike back. He also authorized airstrikes against Yemen but then backed off when costs began to escalate and it became clear to him that Europeans were the main beneficiaries of the operation. In September, the U.S. military began destroying boats it says were carrying narcotics from Venezuela, a country with no ability to meaningfully retaliate against the United States. And Trump’s appetite for risking confrontation with bigger powers is extremely limited, as demonstrated by his reluctance to confront Russia over Ukraine.

HOLDING ON FOR DEAR LIFE

Even though the risk of U.S. disengagement—foreshadowed by the first Trump administration—has been growing for years, most U.S. allies have never truly prepared for it. European defense spending rose modestly after the 2014 Russian invasion of Crimea, but there has been little progress on developing a “European pillar” within NATO, which would enable European militaries to operate more independently from the United States. While France has long called for European “strategic autonomy,” other countries on the continent have waved off the idea as either unnecessary or too expensive.

U.S. partners in Asia and the Middle East also spent the past decade focused far more on maintaining their alliances with the United States than on supplementing or replacing them—a reasonable choice, given the substantial resources and political will necessary to develop alternatives to U.S. leadership. But now, faced with the risk that the United States will abdicate its leadership role or refuse to defend U.S. partners, they are short of good options.

So far, during the second Trump administration, most U.S. allies and partners have continued to cling to U.S. support, sometimes desperately. NATO members, for example, have bent over backward to satisfy Trump by agreeing to increase their defense spending to five percent of GDP by 2035—a major achievement, even if reached with financial sleight of hand. (Spending on infrastructure counts toward the five percent.) Many leaders have tried flattery to keep Trump on board. This approach is best exemplified by NATO Secretary-General Mark Rutte, who in June sent Trump an obsequious message praising his Middle Eastern diplomacy and lauding him for getting European countries to spend more on defense. “Europe is going to pay in a BIG way, as they should, and it will be your win,” Rutte wrote. Similarly, in their first meetings with Trump, Japanese Prime Minister Sanae Takaichi said she would nominate him for a Nobel Peace Prize, and South Korean President Lee Jae-myung told Trump that he was “the only person who can make progress” toward peace between North and South Korea.

Allies have also used economic deals to try to keep the United States committed to their security. Japan, South Korea, and the European Union have all agreed to unfavorable trade agreements with Washington, in which they have accepted big increases in U.S. tariffs and pledged massive investment in the U.S. economy and purchases of American energy exports or military goods. These deals were designed, in part, to avoid a trade war but were also motivated by concerns that a major trade dispute with the United States could undermine the close security partnership with Washington on which all these allies depend. As EU Council President António Costa acknowledged in September, “Escalating tensions with a key ally over tariffs, while our Eastern border is under threat, would have been an imprudent risk.” Any prospect that the EU would stand up to U.S. tariffs—as China did—was undermined by “fears that Trump would cut off weapons supplies to Ukraine, pull troops out of Europe, or even quit NATO,” as the Financial Times put it.

Likewise in the Middle East, Gulf countries have tried to keep Trump interested in their security with fawning and pledges to invest hundreds of billions of dollars in the United States. Qatar even gifted Trump an airplane for his personal use, signed up to a vague “economic exchange” of $1.2 trillion, and assisted Trump in pursuing a cease-fire in Gaza, for which it was rewarded in September 2025 with a U.S. promise to treat an attack on Qatar as a threat to the security of the United States. Other Gulf countries, including Saudi Arabia and the United Arab Emirates, have agreed to real estate and cryptocurrency deals with members of the Trump family and the families of other senior Trump officials, presumably hoping that it will help keep the administration on their side.

FLATTERY GETS YOU NOWHERE

U.S. allies cannot be faulted for seeking to placate Trump. They have few good alternatives to relying on the United States for their security and prosperity. But they should have no illusions: Trump is transactional, defines national interests narrowly, and is loyal only to himself. Flattery and headline-grabbing investment pledges can perhaps help promote positive meetings or notional agreements, but they can hardly ensure enduring support.

It is, in fact, no longer far-fetched to imagine a world in which former allies see the United States as not just unreliable but also unpopular and even adversarial. Trust in the United States has collapsed. According to a survey of people in 24 countries published by the Pew Research Center last June, large majorities in most of the surveyed countries reported they have “no confidence” in Trump to “do the right thing regarding world affairs.” Early in Trump’s second term, Germany’s incoming chancellor, Friedrich Merz, said it was clear that Washington is “largely indifferent to the fate of Europe.” It is not difficult to picture other world leaders reaching similar conclusions about how the United States views their regions.

For now, many U.S. allies feel threatened by China and Russia, making it unlikely that they would go so far as to team up with Beijing or Moscow to balance against the United States. And most Asian and European partners probably won’t join alternative geopolitical groupings such as the BRICS—a ten-country bloc named for its first five members, Brazil, Russia, India, China, and South Africa—given their differences with those countries and their desire to avoid a major crisis with Washington. But an “America first” strategy taken to its logical extreme could force U.S. allies to distance themselves from the United States to a degree that would have been virtually unthinkable during the past 80 years.

More than 70 percent of South Koreans want their government to get nuclear weapons.

Alternatives to relying on the United States each present major challenges, but U.S. partners may have little choice but to pursue them. Many are already developing more independent and capable militaries, increasing defense spending, and beginning to integrate with other partners. The EU, for example, has a number of initiatives in place that will increase defense spending and military integration by 2030, and Japan has pledged to raise its defense spending to two percent of GDP by March 2026.

If managed well, such efforts could lead to more balanced and equal partnerships with the United States. But they are unlikely to leave Asia and Europe more secure. There is nothing that U.S. allies can realistically do in the short term to compensate for the loss of a reliable defense commitment from the United States. And if the United States is less willing to protect allies, those allies may be less likely to help the United States. Not long ago, numerous Asian, European, and Middle Eastern partners were ready to send their troops to fight and die alongside those of the United States out of allegiance to Washington. But those days may be over.

Greater self-reliance will also likely lead allies to develop defense industries less dependent on the United States. As they spend more scarce resources on defense, EU members have agreed that major categories of funding can be spent only within the EU (or in certain partner states, such as Norway, but not the United States). Germany plans to spend the vast bulk of some $95 billion in arms purchases in Europe, with only eight percent going to U.S. suppliers. And it was no coincidence that Denmark, resentful of Trump’s threats against Greenland, decided in September 2025 to make its largest ever military purchase—over $9 billion in air defense systems—from European ventures, not American ones.

Some allies may also seek to develop their own nuclear weapons. More than 70 percent of South Koreans want their government to get the bomb, according to polling published in 2024 by Gallup Korea. Although a majority of people in Japan oppose nuclear weapons, more are becoming open to the idea of their country developing its own. In Europe, doubts about U.S. extended deterrence prompted Merz to raise the possibility that France and the United Kingdom might supplement the American nuclear shield. In March, Polish Prime Minister Donald Tusk said that “Poland must pursue the most advanced capabilities, including nuclear and modern unconventional weapons.” And in September, just after Israel launched airstrikes on Qatar—an attack the United States did not prevent—Saudi Arabia signed a defense agreement with Pakistan. Pakistan has said that, under the deal, it could make its nuclear deterrent available to Saudi Arabia if needed.

Rutte and Trump in Washington, D.C., October 2025

Trump and NATO Secretary General Mark Rutte in Washington, D.C., October 2025

Kevin Lamarque / Reuters

Replacing the U.S. nuclear umbrella will be politically difficult, technologically challenging, and exceedingly expensive. It might not even prove effective at deterring adversaries, because the small non-U.S. nuclear forces would be overwhelmed by the much larger arsenals belonging to China and Russia, the most likely aggressors. But over time, U.S. partners will have to take seriously the possibility that they will need their own nuclear forces because the United States will refuse to defend them.

The erosion of U.S. leadership and reliability will have major implications for the world economic order, as well. For the most part, the United States’ allies in Asia and Europe have decided to accept one-sided trade deals rather than join forces against the United States, but their calculus might change. When Trump, during his first term, pulled the United States out of the Trans-Pacific Partnership—a major U.S.-led trading bloc designed in part to counterbalance China—Australia, Canada, and Japan stuck with the pact. A few years later, many of the same countries joined China in the Regional Comprehensive Economic Partnership, now the largest free-trade agreement in the world—and one that does not include the United States. The less U.S. partners rely on the United States for security, the easier it is for them to work with one another, or with other great powers, to balance what they see as hostile economic policies coming out of Washington.

As the old order collapses, the world could become a scarier place. And even if allies come up with a Plan B, they might not be able to handle increased aggression on their own. This is not the first “America first” policy inflicted on them. During the early decades of the twentieth century, many in Washington took a similar approach, based on high tariffs, an aversion to alliance commitments and foreign wars, and a desire to appease rather than stand up to autocratic powers. The results paved the way for global aggression in the 1930s. Without Washington’s support, American allies were unable to do anything about it.

No one should wish to see the end of a U.S.-led alliance system that, for all its weaknesses, costs, and imbalances, has served Washington and its partners well for several generations. But no one should count on it to endure, either. The second Trump administration is not committed to defending that system, and there is no guarantee that the next president will be.

None of this means that cooperation with Washington will be impossible. The United States will remain an important, if perhaps much more transactional, partner for years to come. But it does mean that allies can no longer count on the United States to devote significant resources to defending them or the world order. Allies’ Plan A should be to do everything in their power to preserve as much practical cooperation as possible. But it would be dangerous and irresponsible not to have a Plan B.