Future high school students be forewarned: You will have another corollary to the Monroe Doctrine to memorize before your U.S. history exam. Last week, on the 202nd anniversary of President James Monroe’s 1823 declaration, the White House rolled out a new “Trump Corollary” of its own.
Presented under the label of “America 250,” the announcement connected contemporary politics to an imagined national past. Yet the thinness of President Donald Trump’s history doesn’t mean his announcement won’t have real consequences. If he follows his message with military intervention in Latin America, Trump, like his some of his predecessors, will discover that the public’s enthusiasm for patriotic doctrines doesn’t translate to support for ill-conceived wars.
Future high school students be forewarned: You will have another corollary to the Monroe Doctrine to memorize before your U.S. history exam. Last week, on the 202nd anniversary of President James Monroe’s 1823 declaration, the White House rolled out a new “Trump Corollary” of its own.
Presented under the label of “America 250,” the announcement connected contemporary politics to an imagined national past. Yet the thinness of President Donald Trump’s history doesn’t mean his announcement won’t have real consequences. If he follows his message with military intervention in Latin America, Trump, like his some of his predecessors, will discover that the public’s enthusiasm for patriotic doctrines doesn’t translate to support for ill-conceived wars.
The original Monroe Doctrine of 1823 declared the Western Hemisphere off limits to European colonization in order to safeguard the security of the relatively weak United States. But Monroe stated only what European powers were not allowed to do; he did not outline U.S. policy, let alone set about to create a binding foreign-policy doctrine.
Ever since, the legacy of the Monroe Doctrine, and the new corollaries attached to it, has been one of U.S. policymakers presenting their activist agendas under the umbrella of Monroe’s anti-imperial banner. The most famous corollary to date was the Roosevelt Corollary of 1904, in which the United States asserted the privilege of unilaterally intervening in, and occupying, indebted and unstable Caribbean nations to prevent European powers taking such actions themselves.
The interesting thing about the new Trump Corollary is that it fudges the critical matter of what policies and actions it is calling for. The corollary consists of a muscular, if vague, assertion: “That the American people—not foreign nations nor globalist institutions—will always control their own destiny in our hemisphere.” Trump’s brief announcement then cites the non-colonization clause of Monroe’s original message, without saying any else about what actions the United States will take to enforce it.
The Trump Corollary gets its history wrong. It anachronistically asserts that, upon the release of the Monroe Doctrine in 1823, “every nation knew that the United States of America was emerging as a superpower unlike anything the world had ever known.” In truth, the United States in 1823 was hardly a nation at all: It was a weak union of feuding states destined to implode decades later in one of the great civil wars of modern history.
The White House message lists the administration’s achievements and objectives in what it calls “our hemisphere”: asserting privilege over the Panama Canal; restoring “American maritime dominance”; and, ominously, “halting the flow of deadly drugs flowing through Mexico, ending the invasion of illegal aliens along our southern border, and dismantling narco-terrorist networks.”
How seriously should we take this new corollary? Like the corollaries and invocations of doctrine that preceded it, Trump’s statement should first be read in relation to domestic political theater. The Monroe Doctrine has always been a shapeshifting shibboleth subject to the winds of internal politics. Its history is more often than not the story of opportunistic politicians claiming the nationalist high ground, frequently in election years, rather than a diplomatic story about the formulation of a coherent foreign policy. My own study of the doctrine has found that U.S. politicians have invoked it most often against one another, not foreign powers.
In this light, it is no surprise that the Trump team returned to the Monroe Doctrine. It is a U.S. symbol custom-designed for an administration that never lets an opportunity for nationalist flag-waving pass by. The announcement of the corollary might be read as something analogous to using Mount Rushmore as a photo op backdrop, superimposing the stars and stripes on the president’s Truth Social avatar, or commissioning the flawed 1776 Commission to promote nationalist history.
Invoking the Monroe Doctrine carries the added political benefit of trolling the American left, which has long condemned it as a symbol of racist imperialism (John Kerry famously declared the doctrine dead in 2013). Meanwhile, for a president obsessed with his historical legacy, proclaiming a new corollary ensures Trump’s place in the lineup with James K. Polk and Theodore Roosevelt, presidents who used the doctrine to expand U.S. power with chauvinistic swagger.
But none of this means that the Trump Corollary will fade away as quickly as a Truth Social post. Beneath the bombast of the corollary announcement lie the core impulses of Trump’s foreign policy. Trump’s corollary calls for the pursuit of regional domination (“our hemisphere,” as the text puts it). It rewards political allies (Argentina and El Salvador are mentioned positively in the announcement), skewers ideological foes (Venezuela and immigrants), and advances the interests of a key political bloc (Republican-voting Cuban Americans who hope that the new corollary will lead to the rollback of a certain regime off the coast of Florida).
These impulses might lend substance to the corollary. Indeed, the administration two days later followed up its brief anniversary announcement with its 2025 National Security Strategy, which again references the Monroe Doctrine. The strategy focuses far more on Latin America and regional affairs than any other recent document of its kind. Historically minded readers might be forgiven for feeling as if they have entered a time warp and found themselves back in the era of muscular imperialism associated with Theodore Roosevelt. “After years of neglect, the United States will reassert and enforce the Monroe Doctrine to restore American preeminence in the Western Hemisphere,” the strategy proclaims.
That the announcement of the Trump Corollary comes at a fraught moment in regional geopolitics heightens the stakes. U.S. forces are massing in the Caribbean. U.S. drones have killed more than 80 people in legally questionable strikes on boats allegedly carrying narcotics. Meanwhile, in Venezuela, President Nicolás Maduro shows no signs of stepping down, placing his regime on a potential collision course with the Trump administration. Unlike the offhand invocations of the Monroe Doctrine during Trump’s first term, this iteration might portend real, operational intervention.
Yet one wonders whether this administration possesses the focus and stamina to translate its rhetoric into a systematic doctrine. Will this impulsive and erratic president adhere to a coherent national security strategy, or will he cut deals at first chance? The same muzzle velocity that has enabled Trump to avoid scandal has also limited his administration’s ability to communicate and execute policy. And make no mistake: A new program of hemispheric domination will be a protracted, costly, and unpopular project.
It is worth remembering that the instances in which new interpretations of the Monroe Doctrine led to assertive policies have never turned out as planned. Back in the 1840s, Polk invoked the Monroe Doctrine to justify his program of territorial annexation. The United States needed to take California from Mexico, Polk argued, before the United Kingdom or France did the same. But Polk’s use of the doctrine mired the United States in an unpopular war against Mexico, for which the president’s Democratic Party suffered mightily in the 1846 midterms. In the bigger picture, Polk’s war also set in motion a chain of events that led to the Civil War.
In the early 20th century, Roosevelt’s corollary sucked the United States into quagmires across the Caribbean and Central America. These were the “forever wars” of their era—and were just as unpopular. Given Trump’s instinctive opposition to the wars in Afghanistan and Iraq, it is hard to see him launching a new set of forever wars closer to home.
The Monroe Doctrine’s history offers a guide to the possibilities that lie ahead. For most of its 202-year history, Monroe Doctrine talk has been largely political theater. The White House’s recent announcement might amount to no more than another act in that long production—after all, Trump is the ultimate political showman.
Yet every so often, a new corollary has signaled a real and risky shift in U.S. policy. Whether the Trump Corollary proves to be another flash in the pan or the beginning of a more consequential strategic turn will depend on the Trump administration’s capacity for sustained focus, ability to absorb geopolitical blow-black, and tolerance for domestic political pain. Let’s hope the White House team is reading up on the doctrine’s history.
