U.S. Global Leadership Falters

The United States has seen itself in a global leadership role for so long, it is hard for many to imagine how a retreat from that role would manifest itself. The United States leapt onto the global stage as the Cold War unfolded, abandoning decades of inward focus. It found both security and purpose restoring war-ravaged countries in Europe and Asia, as well as building the emerging postcolonial countries in Africa and the Middle East. For decades, the United States invested its overwhelming economic and military dominance into shaping a global system that others would feel a stake in sustaining. What many Americans have come to call the “rules-based order” certainly privileged the economic, legal, and governance patterns of the United States and its allies, but it was also constraining. + It led to limits on U.S. action and lent a certain predictability to it.

But for many Americans, and for the Trump administration, the United States has invested too much and reaped too little from subordinating U.S. interests to a so-called “rules-based order” that seemingly lets others take advantage of the United States. For them, the U.S. commitment to international affairs is an elite luxury, not a bedrock concern, and they perceive recent U.S. international efforts as expensive failures—not least multitrillion-dollar efforts in Iraq and Afghanistan in the wake of 9/11 whose results fell far short of expectations.

Amid this international context, the U.S. government's budget is under strain, and that strain will increase in the coming years. With $7.3 trillion in planned outlays in 2025 and only $5.5 trillion in receipts, the U.S. federal budget is far out of balance. A growing cohort of retirees entitled to government support, combined with promises to cut taxes further, will put increased pressure on government spending. The calls to focus on curtailing foreign engagement are likely to survive long beyond when the Trump administration's term ends in January 2029. +

The effects of a U.S. pullback in international affairs would not be evenly distributed. Given a deep and bipartisan consensus that China represents the largest challenge to U.S. global interests, the United States will almost certainly maintain a strong if not growing military commitment to the western Pacific. + India's growing economy, combined with its increasingly agile diplomacy and its sometimes-strained ties to China, will draw increased U.S. attention in the coming years, too, as will rising economies in Southeast Asia. For countries in the Pacific, it may feel in many ways like the United States has not pulled back at all.

But for much of the rest of the world, the United States would likely be felt less + The voices of Americans who have argued for more than a decade that the United States has been overcommitted to the Middle East would rise, and the time and attention the United States pays to Africa and Latin America would fall. Not only would Europe be expected to fend more for itself, but the intra-European rivalries and tensions that had been blunted under three-quarters of a century of U.S. primacy would flourish. +

Russia and China would seek to expand their ties further into regions that feel newly neglected. + Even more importantly, a growing number of governments would seek to expand their own ties with Russia and China, partly to hedge against U.S. abandonment, but also to gain leverage against a newly hegemonic United States that feels less bound by international rules. Regional hegemons would almost certainly seek to fill the vacuum the United States has left in its wake, requiring regional states to make new accommodations to their interests. +

U.S. commitment to international organizations could also shrink, which would be felt both in terms of diplomatic attention as well as budget support. + The United States is the largest contributor to the UN system, paying just under a quarter of the organization's expenditures. The United States spent more than $15 billion on humanitarian assistance in 2023 (including more than $10 billion in voluntary contributions to UN agencies such as the World Food Programme, UNICEF, and the UN High Commissioner for Refugees) and about $10 billion more on global health. The U.S. role supporting the orchestration of such assistance could also diminish, reducing the efficiency and effectiveness of aid missions. +

The broader economic effects of a more unilateral U.S. approach to international affairs are unclear. We should expect some slowdown in U.S. efforts to integrate global financial networks, and an increase in transparency is expected, combined with an increased effort by others to create parallel institutions. Trade would likely grow more regionalized as the security of sea lanes diminishes and the robustness of global free trade efforts languishes (or potentially withers under U.S. assault). The United States would also emerge as a more aggressive trading partner, using the size of its domestic market to win concessions for U.S. exporters.

While none of this necessarily would lead to warfare, there would be a period of adjustment and volatility as the world settles into a new equilibrium. Throughout, and perhaps even afterwards, governments would need to put a premium on hedging and agility, and businesses would be evaluating their prospects in a higher-risk environment. + Of course, returns would be higher for some, but probably not for all.