As the world evolves, the United States must adapt or suffer the consequences. The process of adaptation, however, is usually plodding, if it happens at all. Presidents Donald Trump and Joe Biden each attempted to steer U.S. foreign policy in new directions but met resistance from both domestic and foreign actors. The difficulty they encountered is no surprise. Since World War II, many U.S. leaders have attempted to change the country’s foreign policy, and their efforts have often fallen short. Inertia is a powerful force.

Take the two-decade war in Afghanistan as a recent example. For years, the U.S. operation was failing, with little prospect of stabilizing the country and securing a democratic government. Yet bureaucratic and political interests in Washington obstructed efforts to change course. President Barack Obama and his successor, Trump, both talked about ending the war, but ultimately just reduced troop levels. Biden finally completed the U.S. withdrawal in 2021, honoring a deal Trump had made with the Taliban. When the withdrawal got messy, however, Biden ended up paying a political price, even though the policy had high public support.

But the war did end, showing that meaningful shifts in U.S. foreign policy are not impossible. This is good news, because large adjustments are now needed. The era in which the United States could police the world is over, and Washington finds itself embroiled in conflicts it has diminishing capacity to resolve. Many analysts are thus calling for a major strategic reorientation—whether, for example, by enlarging the U.S. military so that it can sustain fights in multiple theaters or by handing off some burdens to U.S. allies and partners. Come January, Trump or his opponent in the 2024 election, Vice President Kamala Harris, could try to make big changes. Any effort to steer U.S. foreign policy in a new direction is sure to encounter formidable obstacles, however, and the new president will need a plan to overcome them.

THE SOURCES OF AMERICAN INERTIA

U.S. foreign policy is made in an institutional ecosystem conceived during World War II, expanded during the Cold War, and maintained through the post–Cold War period of American hegemony. The bureaucracies that design and implement foreign policy, including the Defense Department, the State Department, and the intelligence agencies, have been essential to making the United States powerful and capable. But strong bureaucracies are also conditioned to preserve the existing way of doing things. Each agency naturally safeguards its mission and resources, and major change is always a threat to someone.

As a result, bureaucratic resistance has frequently stymied change in Washington. President Jimmy Carter tried to withdraw U.S. forces from bases in South Korea in 1977, Obama attempted to close the Guantánamo Bay detention center in 2009, and Trump announced that U.S. forces would withdraw from Syria in 2019—but none of these efforts succeeded. Each time, the bureaucracy pushed back and won. Officials leak information to the public and slow roll or even defy orders. This behavior can look like partisanship, a charge Trump levied while president. In fact, it is often simply what the U.S. bureaucracy is programmed to do.

Congress can also block presidential ambitions. The presidency holds immense power, but the legislative branch can derail changes to budgets, treaties, or administrative authorities. These areas of congressional jurisdiction are precisely those that matter for making major change. Congress may obstruct a presidential agenda for purely political reasons, especially if the opposing party controls the House of Representatives or the Senate. Senior congressional leaders who have been in office for decades command the national security committees and may hold entrenched views. Foreign governments and the private sector, meanwhile, lobby Congress to protect policies that favor them, inhibiting changes that may serve the broad public interest but challenge special interests.

In a system already resistant to change, human psychology reinforces inertia. Human sociability, conformism, and the sunk cost fallacy—which leads people to double down on a failing course of action—all contribute to maintaining the status quo. Officials and experts often try to make new facts fit their existing theories rather than adapt their theories to emerging realities. If they start to think differently, they encounter pressures to stop. Change may require admitting mistakes, which people usually don’t like to do. Politicians who revise their views stand out and become vulnerable to charges of flip-flopping. Analysts have incentives not to disagree too sharply with the rest of the foreign policy community, lest they be disqualified from jobs inside or outside government. And mainstream media outlets tend to seek out former government officials for commentary, creating an echo chamber that reinforces conventional wisdom.

CONSPICUOUS OBSTRUCTION

The forces that obstruct change were conspicuous during the Trump and Biden years. Both presidents sought to turn U.S. attention toward Asia while reducing the country’s role in the greater Middle East and limiting its defense commitments in Europe. Both struggled to achieve their goals.

The policymaking system in Washington thwarted some of Trump’s main initiatives. His attempt to withdraw U.S. forces from Syria came to naught after it elicited stark resistance from the military and little support from congressional Republicans. Eyeing a drawdown of U.S. forces in Europe, Trump cut the bureaucracy out and made the decision himself in the Oval Office. But foreign allies diluted his effort: the Polish government convinced Trump to shuffle some troops from Germany to Poland rather than remove them from the continent. One major foreign policy change Trump did manage to execute was to withdraw from the Iranian nuclear agreement. In that case, factors within the system worked in his favor: ditching the deal was a long-standing objective among Republican lawmakers and parts of the bureaucracy.

Biden, for his part, took office intending to follow through on the Obama administration’s “pivot to Asia,” but he ended up expending enormous political, financial, and military capital in the Middle East and Europe. After ordering the withdrawal of U.S. forces from Afghanistan in the first year of his term, Biden saw his approval ratings fall sharply as the Afghan government swiftly collapsed and U.S. personnel scrambled to evacuate. The pain of that experience dampened any enthusiasm for taking risks with further military pullbacks. At the outset, his administration aimed to right-size the U.S. posture in the Middle East, but in the end not much changed on the ground. This left U.S. forces dangerously vulnerable to attack by Iranian-aligned groups in the wake of Hamas’s assault on Israel in October 2023, increasing the stakes of the subsequent conflict for the United States. Unwilling to pay the price of backing away, the Biden administration wound up committing the United States more deeply to the Middle East, including by proposing a defense treaty with Saudi Arabia and sending aircraft carriers and 6,000 additional U.S. personnel to the region.

Similarly, Biden initially sought a “stable and predictable” relationship with Russia that would allow the United States to limit its involvement in European security. But after Russia invaded Ukraine in 2022, Washington assumed a larger and costlier role than before. Biden has now increased U.S. troop levels in the region, supplied Ukraine extensively in its war effort, and toyed with a security guarantee for Kyiv. The administration took all these steps even though it ruled out the direct use of force against Russia and continued to insist that its primary focus lay in Asia.

Of course, Russia’s shocking invasion and Ukraine’s heroic defense demanded U.S. attention. But leading the way in providing aid to Ukraine, pledging U.S. support “as long as it takes,” and leaving the door open to Ukraine’s NATO membership were not the only possible responses. For example, the Biden administration could have put more energy into fostering negotiations between Russia and Ukraine, rebuffed Kyiv’s stated aim of recapturing all its territory, ruled out any postwar commitment to defend Ukraine with U.S. forces, and launched a transition to European leadership of European defense. Washington’s foreign policy operating code kicked in, however, encouraging Biden to put the United States at the center of a campaign, reminiscent of the Cold War, to rally the free world and contain Moscow’s authoritarian aggression.

MAKING CHANGE HAPPEN

Given the strength of the forces favoring continuity in U.S. foreign policy, the administration that enters the White House in January will need a plan if it wants to make any major changes. But a realistic plan should not count on sidelining or transforming the bureaucracy. Although previous U.S. presidents have had some success in using secrecy, as Richard Nixon did in bombing Cambodia and opening diplomacy with China, such tactics risk provoking bureaucratic defiance and congressional pushback, both of which limited Nixon’s achievements. Some advisers in Trump’s orbit hope to get around this problem in a potential second term by gutting the civil service, but that approach comes with a significant downside: the more Trump staffs the bureaucracy with inexperienced loyalists, the less competent these agencies will be to implement whatever policy change he wants.

The better approach is to get key agencies on board with the president’s preferred policy. The White House must identify influential bureaucrats and convince them that change serves not only the national interest but also their agencies’ interests. To counteract the Pentagon’s investment in the war in Afghanistan, for example, White House officials’ best argument to defense leaders would have been that continuing the war would reduce the military’s readiness for great-power competition.

Sometimes agents of change should work across multiple agencies through formal or informal channels. At the beginning of the Cold War, the State Department’s director of policy planning, Paul Nitze, collaborated with like-minded officials in the State and Defense Departments to develop the policy document NSC-68. President Harry Truman ultimately adopted it over the opposition of other top officials, producing a more expensive, militarized, and globe-spanning U.S. national security strategy. Under President Bill Clinton, advocates of NATO enlargement in the National Security Council and State Department were losing the debate until they persuaded the president to sound supportive of enlargement and then convinced the bureaucracy that it was time to implement the president’s policy.

Policymakers must also design and articulate their proposals with human psychology in mind. To overcome bias in favor of the status quo, they can map out a path of gradual change or frame the new policy as a mere update to existing policy. Proponents of expanding NATO membership, for example, began with admitting the Czech Republic, Hungary, and Poland—three of the strongest candidates—into the alliance in 1999 while leaving the door open to other countries in the near future. When the alliance added seven more members in 2004, the move encountered far less opposition within the United States than before.

Policy change is often best presented in ways that harness loss aversion, the psychological tendency to assign greater significance to avoiding losses than to making gains of equal magnitude. Rather than promising the moon, agents of change ought to highlight the ways that their preferred policy can prevent negative outcomes. Leaving Afghanistan, for instance, offered no prospective benefits for the United States or its Afghan partners, but the withdrawal did keep the United States from squandering even more lives and money. In this case, officials’ loss aversion may have helped to overcome the countervailing pressure of the sunk cost fallacy; the argument to avoid future failures became more salient than the pressure to redeem past failures.

Finally, a change-seeking administration must seize on crises when they arise. Most significant U.S. foreign policy shifts since 1945 have come in times of upheaval. The outbreak of the Korean War in 1950, for example, was what finally convinced Truman to adopt NSC-68 after he had previously shelved the policy. The 9/11 attacks in 2001 pushed President George W. Bush to reorganize the U.S. intelligence community, launch the “war on terror,” and invade Iraq.

Crises enable change, but they do not predetermine what that change will look like. Often they elevate ideas, including the recommendations of NSC-68 and the invasion of Iraq, that were conceived before the events that triggered their adoption. A crisis comes with a window to debate the proper response, and advocates of policy change must be ready to take advantage. But they should beware: a solution that goes in search of a problem may cause new and bigger problems. Policymaking during a crisis carries other hazards, such as a bias toward action that can encourage rash decisions.

Even when the best-laid plans encounter the most favorable circumstances, foreign policy shifts bring political risk. If the next president wants to make change, he or she must be ready to spend precious political capital. Incoming administrations often prioritize domestic issues and take the path of least resistance on foreign policy. But deferring difficult foreign policy choices leaves the United States with worse options later on. For instance, the Biden administration never decided whether it would pay the political price of reentering the Iranian nuclear deal after Trump’s exit. Soon the opportunity dissipated and Tehran’s uranium enrichment advanced; now violence between Iran and U.S. regional partners is escalating and Iran’s incentives to cross the nuclear threshold are much greater. The cumulative effects of American inaction amount to self-injury. Because neglect could come back to haunt a president before the end of his or her term, a new administration should do the difficult work of changing policy proactively.

2025 AND BEYOND

A Harris or Trump administration will have several opportunities to shift course, and although no change will be easy to achieve, some methods will work better than others. One looming question is what to do about Ukraine. If the next president seeks to end the war in the near term, he or she will face determined opposition at home from elements of the bureaucracy and members of Congress. Other countries with a stake in the conflict—Ukraine and Russia, as well as NATO members—could also try to obstruct efforts to terminate the war by making public appeals, leveraging their influence in Washington, and mounting influence operations within the United States. Breaking the taboo on diplomatic negotiations could be difficult. The American president would need to speak to domestic and international audiences about the increasing cost and risks of continuing the conflict and would have to cast a pragmatic settlement as the least bad option for the United States, NATO, and Ukraine. Rather than wholly repudiate prior U.S. strategy, the new administration should highlight how its approach would serve Washington’s principal aims since the beginning of the war in 2022, namely avoiding a direct war between NATO and Russia, preserving a sovereign and independent Ukraine, and strengthening Ukraine’s position at the negotiating table.

A Trump administration—and potentially a Harris administration, too—may also wish to see NATO allies shoulder more of the defense burden in Europe. Some speculate that Trump could unilaterally pull the United States out of NATO or yank large numbers of American troops out of Europe. But such drastic moves would produce enough resistance in Congress and the bureaucracy, as well as among U.S. allies, that the gambits would likely fail. To actually draw down the American presence on the continent, a new administration would need a plan to gradually shift the responsibilities and capabilities for defending Europe onto European countries. An incremental approach would help minimize domestic opposition, reduce the risk that Russia would take advantage of a security vacuum, and give Europe time to build up its defense-industrial base.

If Harris wins, she may want to exert more pressure than Biden has mustered to get Israel to agree to a cease-fire with Hamas or Hezbollah or to reduce the civilian harm caused by Israeli military campaigns. She could also expand U.S. sanctions on violent Israeli settlers in the West Bank. Washington’s foreign policy apparatus would resist such moves strenuously, given the enduring support for Israel in both parties, reinforced by pro-Israel groups on Capitol Hill. But with political will, a plan to persuade bureaucratic actors, and a gradual but firm approach, a Harris administration could meaningfully shift policy. Biden, like Obama before him, tried to change Israeli behavior only toward the end of his administration, thereby limiting his leverage on an Israeli government prepared to wait him out. But Harris need not face the same constraint. She could begin her term insisting on certain bottom lines, such as halting settler expansion and violence in the West Bank and taking other credible steps toward a two-state solution. This would leave her enough time to push through any domestic backlash before facing reelection. Trump, on the other hand, might give the Israeli far right license to accelerate efforts to drive Palestinians from their lands, an outcome that could intensify calls to rethink U.S. support for Israel within the Democratic Party and thereby deal lasting damage to U.S.-Israeli relations.

In addition, Harris might buck pressure in Washington to get ever tougher on China, choosing instead to build on Biden’s recent diplomatic progress with Beijing. Trump, too, could try to focus on fighting a trade war while moderating U.S.-Chinese security competition. Either administration could take a more reassuring line on Beijing’s core interests, including by lowering the temperature over Taiwan with a sincere effort to resuscitate the United States’ “one China” policy. Politicians from both parties, especially the opposing party, would accuse the president of weakness. To counter them, Harris or Trump could warn Americans that the costs of a hot or cold war with China would be steep, and that such a conflict could arrive soon if bilateral ties keep deteriorating. The next administration could also make clear to the bureaucracy that couching every pet initiative as a means of pushing back against China would no longer be effective in garnering White House support.

BREAK THE CYCLE

History is replete with the remains of empires that were imprisoned by habit. From the Romans to the Habsburgs, fighting continual wars on multiple fronts against multiple foes led to mounting debts and eventually to irreversible decline. U.S. foreign policy today risks meeting the same fate. Washington appears stuck, reacting to events rather than shaping them, in a spiral that only gets worse as geopolitical divisions deepen, global challenges mount, and the American people turn inward. The United States cannot continue trying to keep the peace everywhere, all at once, at current levels of exertion—and there is no sign that American citizens are willing to spend and sacrifice much more for the privilege.

Changing this dynamic will be difficult, but change is sorely needed. The country deserves leaders who recognize that need. But more than that, the next president must make a plan to overcome the forces keeping U.S. foreign policy on its current path, and then see it through.