Trump’s second-term foreign policy asserts U.S. hegemony in the Western Hemisphere while exploring a great power system based on spheres of influence. Its success hinges on defining these spheres—especially between the U.S. and China—without destabilizing East Asia.
(Photo: Cover of The Economist, March 1-7th, 2025)
During the initial weeks of his second term, U.S. President Donald Trump seemed to highlight two major themes in his foreign policy. One was to assert total, flagrant U.S. hegemony in the Western Hemisphere. The other theme was to hint at Washington’s willingness to transform the international system into a new arrangement that emphasized an outsized role for a handful of great powers. Implicitly, that small, select roster of powerful nations would exhibit at least a modicum of respect for their respective spheres of influence.
Trump was not the least bit subtle about expressing the goal of utter dominance for the United States in the Western Hemisphere. A series of his speeches made that desire indisputable. Trump’s vow to acquire Greenland from Denmark, even if he had to put intense pressure on Copenhagen, was a very clear signal of intent. His loose talk about the alleged fragility of Canada’s unity and Washington’s receptivity to admitting some provinces as new U.S. states was even more revealing. His stated objective to re-take control of the Panama Canal and the revival of the threat made during his first term – to consider using the U.S. military to combat Mexico’s drug cartels – further underscored that the foundation of his foreign policy would be hemispheric hegemony.
At the same time that Trump was emphasizing renewed U.S. dominance in its geostrategic neighborhood, however, he was reaching out with conciliatory messages to other countries that Washington viewed as the principal global powers. It was no accident that among the earliest calls from the Oval Office were those to Vladimir Putin, President of the Russian Federation, and Xi Jinping, President of the People’s Republic of China (PRC). Those actions hinted at a possible fundamental shift in Washington’s overall foreign policy. Instead of clinging to the usual strategy of emphasizing close relations with traditional U.S. allies in Europe and East Asia, Trump appeared to be signaling that he envisions a new system based on a concert of great powers and respect for the concept of spheres of influence. The model for such an approach would be the system adopted and maintained by Europe’s great powers from the end of the Napoleonic wars to the onset of World War I.
It may be too early to tell if that is what Trump truly has in mind, but there are some intriguing signs coming from the administration, and smaller U.S. allies in both Europe and East Asia are beginning to hedge their bets about the durability of Washington’s security guarantees. Officials in Taiwan’s government are already quietly expressing concerns about the reliability of Washington’s informal, but strongly implied, commitment to the island’s security. South Korean leaders appear to harbor similar doubts about the solidity of Washington’s security shield under the existing bilateral alliance. Advocates in South Korea who believe that Seoul should build its own nuclear deterrent are again becoming more vocal.
The turbulence in Washington’s relations with its NATO allies is even more pronounced and public. Trump now demands that NATO’s European members increase their annual defense spending to a minimum of 5 percent of Gross Domestic Product (GDP). The president’s position is a major escalation from his previous demand that the allies all fulfill their earlier promise to devote at least 2 percent of GDP to defense. However, European leaders, including Ursula van der Leyen, the head of the European Commission, seem inclined to accept Trump’s challenge. She has proposed a Rearm Europe Act that would boost European Union (EU) military outlays to $800 billion per year—nearly as much as the projected U.S. budget. In addition, French president Emmanuel Macron has stated that he is willing to consider extending France’s nuclear deterrent to cover his country’s European neighbors.
At that point, the EU, plus Britain, would be in position to make Europe an independent player in any new concert of great powers. Given the mounting policy differences between Washington and its principal European allies, Trump does not seem unduly concerned if that development takes place. Indeed, a stronger, independent European pillar would be quite consistent with a new international order based on cooperation among the handful of truly powerful countries.
The presence of the United States, the PRC, Russia, and a resurgent Europe would certainly constitute a credible core for such a new concert of great powers. However, one major potential impediment would be how to delineate spheres of influence, and East Asia might prove to be the most difficult arena of all for carrying out that process. For example, how would it be possible to draw clear lines of control between Japan and the PRC given their close geographic proximity? It also seems rather unlikely that Japan will forever be content to be the only major power in the region without nuclear weapons. That is especially true if Beijing’s already sizable nuclear arsenal continues to grow.
The biggest question of all would be what role the United States intends (and is able) to play in East Asia in a system based on great power spheres of influence. It would be unsustainable for American leaders to insist on U.S. hegemony in the Western Hemisphere but not accept the PRC being at least the leading power, if not the hegemon, in East Asia. However, reducing Washington’s demands and expectations in the region would inevitably have major real world consequences not only for Japan, South Korea, and other countries, but especially for Taiwan. It would be hard to visualize a great power peace, if the United States maintains a huge military presence in East Asia. That policy would be even harder to sustain if the principal purpose is to preserve and defend Taiwan’s de facto independence. Beijing and Washington must reach a mutually acceptable understanding about Taiwan’s future status, and that will be an extraordinarily difficult challenge.
The Trump administration’s apparent flirtation with the concept of a peace based on respect for a handful of great powers and their various spheres of influence is mildly encouraging. The age of Pax Americana is fading, and it is not clear yet what will replace it. Perceptive experts in international affairs understood, though, that change was inevitable someday. Charles Krauthammer was wise enough to title his seminal article in Foreign Affairs, “The Unipolar Moment,” [emphasis added]. That moment is coming to an end. Trump has exhibited some valid instincts about making the needed adjustments, but they appear to be little more than instincts yet. A good place to begin making the needed reforms more substantive would be to better define the respective spheres of influence between the PRC and the United States.
