By the end of 2024, the postwar liberal international order seemed to be eroding day by day, pillar by pillar. And yet, perhaps the most noteworthy element of that order continues: the persistence of great power peace. From 1945 to the present—80 years this summer—no two states considered to be great powers have fought a war against each other. To be sure, the U.S. and the USSR came close a couple of times during the Cold War. And they did battle through proxies. But they never fought each other directly. The rise of China in this century has undeniably led to an increase in great power tensions but, again, no actual war has been waged.
One could argue that streak will continue in 2025. After all, for all of U.S. President Donald Trump’s bluster, he campaigned for office in 2024 on a foreign policy of restraint. In his stump speeches, he constantly warned that the U.S. is “at the brink of World War III,” but he also repeatedly promised that he would prevent it. While still his running mate, Vice President JD Vance insisted that Trump was “the candidate of peace.” Respectable foreign policy observers like the Financial Times’ Gideon Rachman wrote back in November that “Trump’s instinct is to stay aloof from foreign conflicts.” Dan Caldwell, an Iraq War veteran and public policy adviser at Defense Priorities—a pro-restraint advocacy group—echoed the thought, telling Rachman that “[Trump’s] instinct has always been to avoid a major war.”
Since winning the election, however, Trump has sounded a slightly different tune, refusing to rule out the use of force to seize control of Greenland and the Panama Canal. His supporters are talking less about restraint and more about how Greenland has a treasure of critical minerals and that possession of it “would make sense … for war purposes.” Foreign leaders are rattled.
What is going on? There are some disturbing parallels between how great powers are behaving today and how they started behaving in the late 1930s. In both eras, the proliferation of economic sanctions and embargoes caused great powers to fear that they would be cut off from critical resources. Their reaction to that threat, in turn, helped to escalate great power conflict. The question today is whether history will repeat itself, or only rhyme.
In his book, “The Economic Weapon: The Rise of Sanctions as a Tool of Modern War,” Nicholas Mulder chronicled how League of Nations sanctions against Italy after its invasion of Ethiopia in 1935 served as an important prelude to the outbreak of World War II. In the end, the sanctions failed to work, but it was a near-run thing. Italy’s exports contacted by more than a third, and Rome was on the precipice of a balance of payments crisis. Benito Mussolini later told Adolph Hitler that had the league successfully expanded the embargo to include oil—it couldn’t because of U.S. non-participation—Italy “would have had to retreat in Ethiopia. It would have been an unmistakable catastrophe.”
Mulder argues that the league’s sanctions against Italy triggered a vicious spiral that made war all the more conceivable, as they “accelerated the search for a very specific form of economic autarky: resilience against sanctions or a blockade that cut off imports of raw materials.” This, in turn, strengthened the appeal of territorial conquest as a way of securing those resources. “Economic pressure, meant to restrain aggressive expansion,” Mulder concludes, “now began to accelerate it.”
There are some disturbing parallels between how great powers are behaving today and how they started behaving in the late 1930s. The question today is whether history will repeat itself, or only rhyme.
Fast forward to 2025. According to Henry Farrell and Abraham Newman, we live in an age of “weaponized interdependence” in which states that control key nodes of networks—and particularly the U.S., given the dollar’s role as the global reserve currency—can engage in some serious economic sanctions. And increasingly, Western sanctions are less a tool of coercion and more a tool of economic warfare. This can be seen in the evolution of justifications for the West’s sanctions on Russia after President Vladimir Putin’s all-out invasion of Ukraine in 2022. First threatened as a form of deterrence, they were then implemented as an instrument of coercion. But they now serve the purpose of weakening Russia’s warfighting abilities. This can also be seen in the proliferation of U.S. export controls placed on China over the past three years.
Against this backdrop, it’s no wonder that in Christopher Miller’s book, “Chip War,” one former official from Trump’s first administration described weaponized interdependence as “a beautiful thing.” But it’s also a very alarming thing.
As with the 1935 League of Nations sanctions on Italy, these U.S. efforts at economic statecraft might not succeed in their purpose, but they have contributed to escalating rounds of economic warfare. Russia has responded with countersanctions as well as attempts to sabotage Western information and transportation infrastructures. Like Russia, China has also ramped up its cyberwarfare and physical attacks on Western infrastructure. Furthermore, Chinese countersanctions, which the New York Times labeled “supply chain warfare,” have been more significant—and more ambitious: For the first time last month, China applied sanctions extraterritorially, forbidding countries from re-exporting critical minerals to the United States.
It is in this context that one must interpret why the incoming Trump administration is articulating a desire to control territories that already belong to treaty allies. Sure, in part this represents Trump’s 19th-century worldview that land equals power. But it also represents the elite fear that the U.S. must secure access to critical minerals and infrastructure to prepare for the possibility of a great power war. This fear can be seen in the laments about the U.S. military’s dependency on “an expansive global supply chain” to stock its munitions and the op-eds with rhetoric like, “We are already in the middle of an industrial war” against a China whose “primary goal is to damage America’s economy and pave the way for China to become the world’s pre-eminent power.”
Moreover, Trump is not the only one applying this logic to U.S. treaty allies along with adversaries and rivals. Progressive defenders of former President Joe Biden’s decision to block Nippon Steel’s acquisition of U.S. Steel argued that the U.S. cannot cede production of primary steel to foreign ownership, because “in a crunch—be that wartime or economic shocks—steel companies tend to fall in line behind their home country governments.”
The international relations literature has been skeptical about the notion that competition over resources is a significant cause of war. However, the caveat is that even great powers will fear being cut off from resources that threaten their military capabilities. Of course, acting on that fear raises the expectations of conflict among peer competitors, fueling a classic security dilemma in which actions designed to ensure a security of supply in times of war heighten expectations of future conflict that risk becoming a self-fulfilling prophecy. The heightening of war expectations is clearly intended to be an act of deterrence; the likelihood of it spiraling out of control under Trump, however, is easy to envision.
For decades, the principal sources of great power peace have been clear: U.S. hegemony, commercial interdependence and nuclear deterrence. But really, there was a fourth pillar as well: whether elites in these countries were seriously contemplating the mechanics of a sustained great power war. For much of the post-Cold War era, that was inconceivable.
In 2025, U.S. hegemony looks wobbly, and great powers are falling all over themselves to reject interdependence unless it favors them asymmetrically. Increasingly, elites in the U.S. and China seem to be conceiving of how a war between the two countries would play out. Which means we may be about to test whether the last pillar of great power peace—the logic of mutually assured destruction—remains compelling or not.
Daniel W. Drezner is distinguished professor of international politics at the Fletcher School at Tufts University. He is the author of Drezner’s World. His WPR column appears monthly.