Donald Trump campaigned for a second U.S. presidential term on a promise to end wars, not start them. And for the first year after his return, there were indications that he might make a real break with the status quo that has led Washington to overextend itself. He pushed the United States’ European allies to spend more on defense, promoted peace talks between Russia and Ukraine, and pursued a cautious détente with China that has dialed down tensions over Taiwan.

Eighteen months later, however, the United States is bogged down in a new war in the Middle East. Although the U.S. military has enjoyed tactical successes, Washington has not achieved any kind of meaningful strategic victory; in certain respects, Iran exerts more power now than it did in February. Nonetheless, Trump has shied away from making diplomatic compromises. Just like his nemesis, U.S. President Barack Obama, Trump promised Americans that he would extract the country from pointless “forever wars” in the Middle East and then proved unable to do so. But the fact that the United States again became mired in a Middle East conflict is even more surprising today, because over the past two decades, the American public as well as many U.S. leaders have firmly concluded that such wars are mistakes.

At heart, structures and incentives pull Washington back, repeatedly, to avoidable quagmires. For starters, military action is easy for U.S. presidents to initiate. Since 1991, U.S. leaders have gotten in the habit of deploying force to secure even the most minor U.S. interests. The short-term costs and risks of using force against a smaller, distant state or nonstate actor often appear small—most Americans can go about their day-to-day lives without even realizing their country is at war—and Congress has largely become willing to cede its constitutional oversight. But getting out of these kinds of conflicts is far harder. Washington is accustomed to setting maximalist goals for even marginal wars, and U.S. leaders balk at halting an intervention without meeting promised objectives. Particularly if the ongoing costs of a conflict are relatively diffuse, there are few incentives for presidents to face accusations of weakness.

Yet the costs of these interventions are not small. They are merely hidden. Repeated wars add to a growing national debt, overstretch the U.S. military, and generate opportunity costs, drawing spending away from needed military investments and domestic priorities. Simply desiring to change the United States’ habit of waging war has not been enough to change it. If U.S. foreign-policy makers want to break the cycle, they need to think of ways to make using force a harder and less attractive option.

The Trump administration’s 2025 National Security Strategy broke with precedent. Most national security strategies populate laundry lists of so-called vital U.S. interests through an interagency process that ensures that no issue goes unmentioned. Last year’s document, by contrast, admitted that the United States has a set of discrete, circumscribed interests that policymakers “must evaluate, sort, and prioritize.” It argued that “not every country, region, issue, or cause—however worthy—can be the focus of American strategy.” And it went on to emphasize the importance of the Western Hemisphere and the Indo-Pacific while concluding that “the days in which the Middle East dominated American foreign policy in both long-term planning and day-to-day execution are thankfully over.”

For much of the first year of his second term, Trump loosely adhered to this stated approach. The White House did use military force abroad, engaging in campaigns to strike Iranian nuclear sites and boats in the Caribbean that were allegedly involved in drug trafficking. But Trump also aggressively pushed allies in Europe and Asia to share the burden of defending their regions and moved to facilitate peace talks in both Gaza and Ukraine. The June 2025 U.S.-Israeli attack on Iran, the so-called 12-day war, was at least brief and its objective specific. Similarly, the January seizure of Venezuelan President Nicolás Maduro by U.S. Special Forces did not attempt full regime change. Instead, the White House struck a deal with Maduro’s vice president, Delcy Rodríguez, to take over.

But the successes in Venezuela and during the 12-day war strengthened the neoconservative wing of the Republican Party and made it easier to argue for subsequent interventions. A mere month after the Venezuela operation, U.S. forces launched Operation Epic Fury, targeting Iranian military infrastructure and killing senior regime leaders; the administration’s early rhetoric openly promised regime change in Tehran. Six months on, the damage to Iran’s military capabilities has been significant. But the United States has expended much of its stockpile of precision munitions and suffered substantial damage to its regional bases. The Islamic Republic remains in power and has expanded its ability to threaten shipping through the Strait of Hormuz.

Structural conditions keep........

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