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.