Trump’s Greenland and Panama Canal Threats Are a Throwback to an Old, Misguided Foreign Policy

At a press conference on Tuesday, President-elect Donald Trump once again vowed to push U.S. foreign policy back to the future. Trump reiterated his desire to reassert U.S. control over the Panama Canal, by military means if necessary; make Canada the fifty-first U.S. state; and annex Greenland for “national security purposes.” Such approaches would be startling departures from the Biden administration’s liberal internationalism—but with deep roots in U.S. foreign policy.

Trump’s determination to treat the Western Hemisphere as a U.S. sphere of influence signals a revival of the Monroe Doctrine, the strategy first introduced by President James Monroe in 1823 that shaped U.S. foreign policy decisively through the early twentieth century and subsequently during the Cold War. Trump’s remarks suggest that unchallenged hemispheric dominance will be at the core of his “America First” approach for the same two motives driving the Monroe Doctrine: to prevent outside powers from meddling and mitigate perceived chaos in the region. Resurrecting this tradition, however, would be both risky and counterproductive to U.S. foreign policy and the global order.

Both Shield and Sword

Two hundred years ago, as rebellions against Spanish colonial rule rocked Latin America, U.S. leaders worried that other European powers might fill the vacuum. To preempt this outcome, Monroe conjured an “American system” in which European powers were forbidden to meddle. He declared that the Western hemisphere would be off limits and put the imperial powers on notice: “We should consider any attempt on their part to extend their system to any portion of this hemisphere as dangerous to our peace and security.”

As U.S. power grew, successive administrations invoked the doctrine not just as a shield, but as a sword. In 1845, President James K. Polk annexed Texas, lest it become “an ally or dependency of some foreign nation more powerful than [the United States].” The next year Polk cited the doctrine to defend a war with Mexico that brought California and the American southwest under U.S. sovereignty. In 1867, Andrew Johnson summoned it in purchasing Alaska.

By the 1890s, the Monroe Doctrine was understood to imply that the entire Western Hemisphere was an American preserve. Grover Cleveland’s administration made this explicit in 1895, intervening in a dispute over the boundaries between Venezuela and British Guiana. U.S. Secretary of State Richard Olney expressed what became known as the doctrine’s Olney Corollary: “Today the United States is practically sovereign on this continent, and its fiat is law upon the subjects to which it confines its interposition.” Lest that pedantic formulation left any doubt, he warned Britain that America’s “infinite resources combined with its isolated position render it master of the situation and practically invulnerable as against any or all other powers.”

Three years later, war with Spain handed the United States the island of Puerto Rico and a new protectorate in Cuba. In the Caribbean basin, it now intervened at will. In 1903, Theodore Roosevelt interceded to guarantee Panama’s secession from Colombia, securing sole rights for the U.S. to build an isthmian canal. The next year he issued his own corollary that the United States, “however reluctantly,” may act as a policing power “in flagrant cases of such wrongdoing or impotence.” Even Woodrow Wilson, who hoped to put inter-American relations on a more progressive footing, fell prey to unilateralist temptations. In 1915, he sent Marines to Haiti to restore political and economic stability. The next year he ordered the U.S. Army into Mexico in a fruitless “punitive expedition” to capture the revolutionary Pancho Villa.

A Shifting Basis for World Order

Even Wilson’s most famous foreign policy initiative—the League of Nations, which he hoped would preserve international peace after World War I—was contorted to fit under the Monroe Doctrine for his domestic audience. Despite the league’s global rather than continental approach, Wilson framed its promise of universal collective security as the logical extension of this regional arrangement: “[N]ations should with one accord adopt the doctrine of President Monroe as the Doctrine of the World: that no nation should seek to extend its polity over any other nation or people.”

Wilson’s realist critics were unmoved. “If we have the Monroe Doctrine everywhere,” retorted Massachusetts Senator Henry Cabot Lodge, “we may be perfectly certain that it will not exist anywhere.” Lodge had a point. A universal collective security system was fundamentally at odds with one of great powers’ spheres of influence. In the end, nationalist anxieties about preserving U.S. hemispheric domination helped doom Senate approval for the League Covenant.

The Monroe Doctrine’s longstanding grip on U.S. foreign policy finally began to loosen in the 1930s, with the election of Franklin D. Roosevelt and America’s subsequent turn to globalism. In his first inaugural address in March 1933, FDR advocated a noninterventionist course in the Western Hemisphere: the “policy of the good neighbor.” Following U.S. entry into World War II, his administration drafted blueprints for an open, rule-bound world order based on collective security and a multilateral commerce. Significantly, FDR rebuffed efforts from Britain and the USSR to negotiate spheres of influence delimiting their postwar regional prerogatives.

The Charter of the United Nations reflected these universalist instincts, and FDR was jubilant. On his return from the Yalta Conference in March 1945, he declared the summit a “turning point” in world history. He predicted the UN would reverse policies of unilateral action, “the exclusive alliances, the spheres of influence, the balances of power” that had been “tried for centuries—and have always failed.”

Yet Yalta quickly became a symbol for what FDR reviled: acknowledgment of a closed Soviet sphere of influence in Eastern Europe, reinforced by the descent of an iron curtain. As for the United States, its own ostensible rejection of spheres proved selective and evanescent. National security officials insisted on retaining U.S. hegemony in Central America and the Caribbean—“Our little region over here which has never bothered anybody,” Secretary of War Henry Stimson quipped. To try to reduce any cognitive dissonance, U.S. officials insisted that these were “open” rather than “closed” spheres, allowing countries freedom in their political and economic choices and international relations.

Once the Cold War began, any U.S. circumspection about the Monroe Doctrine vanished. Washington moved to secure Latin America from communist subversion and Soviet influence, making it “a closed hemisphere in an open world.” It intervened repeatedly against left-wing governments and movements, as in Guatemala, the Dominican Republic, Chile, El Salvador, Nicaragua, and Granada. 

Trump’s Gambits Reconsidered

Viewed through this historical prism, Trump’s pugnacious threats to seize the Panama Canal or use troops to counter disorder in Mexico are less a departure from tradition than a reversion to the norm.

Trump’s blunt insistence that Denmark relinquish Greenland can be seen in the same light. Trump’s ambitions to acquire the strategically located, resource-rich island three times the size of Texas echoes U.S. territorial purchases from previous centuries that were roundly criticized at the time but later regarded as tremendous deals. Most obvious among them were the acquisition of the Louisiana Territory from France in 1803 for $15 million and of Alaska from Russia in 1867 for $7.2 million. Trump, too, isn’t the first president to set his sights on Greenland: Andrew Johnson considered acquiring it 1867, and Harry Truman offered Denmark $100 million in gold for it in 1946. But for now, the island isn’t biting.

Given Trump’s impulsive temperament and capricious style, it is perilous to attribute his utterances to any underlying grand strategy. Still, one thing seems likely: The logic of spheres will be at the core of his approach to world order. This is partly a function of his longstanding aversion toward globalism, multilateralism, entangling alliances, and forever wars in distant countries. Indeed, he would presumably agree with Secretary of State John Quincy Adams’ 1821 adage: “America goes not abroad in search of monsters to destroy.”

Although often interpreted as an expression of isolationism, that line is more accurately read as a warning against imperial overreach. Like Monroe—the president to whom Quincy Adams reported—Trump is no isolationist. He seeks U.S. retrenchment from globalism but insists the United States dominate its immediate neighborhood, to fend off both hemispheric instability and geopolitical adversaries—not least China. Since 2010, China has made major inroads in Latin America, bolstering its diplomatic and commercial presence and investing in massive infrastructure projects. The United States, meanwhile, has long treated the region as a peripheral concern, pursuing a policy of (not so) “benign neglect.”

With Trump’s election, that seems poised to change. Writing back in May 2024, the historian Hal Brands speculated that a second helping of Trumpism “would feature an energized Monroe Doctrine,” with Washington retreating from its longtime alliances in Europe and Asia and instead focusing on “intensified and perhaps heavier-handed efforts to safeguard American influence in the New World, and to prevent rivals from gaining a foothold there.” Although Trump has not yet taken office, this reorientation appears well under way.

But if there is a strong case for Trump to ramp up U.S. focus on the Americas, explicitly reviving the interventionist Monroe Doctrine would be deeply counterproductive. Beyond stimulating anti-American nationalism in the hemisphere, such a throwback policy would legitimate efforts by China, Russia, and potentially other regional powers to pursue spheres of influence in their own neighborhoods, further undermining the UN Charter and the already fraying legal foundations of international order.

Already, Chinese officials and experts liken China’s ambitions and claims in the South China Sea to historical U.S. efforts to  turn the Caribbean into “an American lake.” Trump’s revival of the Monroe Doctrine would also bode ill for China’s neighbors, including U.S. allies such as the Philippines and friendly powers such as Vietnam, which are seeking to resist Beijing’s expansionist aspirations. Russia, meanwhile, has long sought to reclaim influence over its so-called Near Abroad, including Ukraine and other states of the former Soviet Union.

A more farsighted, and promising, U.S. strategy would be for the Trump administration to redouble U.S. diplomatic and economic attention to the Western Hemisphere while formally renouncing the hegemonic presumption inherent in the Monroe Doctrine. As part of this process, the United States should commit itself to bolstering hemispheric institutions that are consistent with the UN Charter, based on mutual respect for sovereignty and collective action. Finally, Trump should take a page from FDR and renounce exclusive zones of great power privilege as contrary to the objective of a stable and just world order. As Roosevelt declared on his return from Yalta—and as subsequent history would bear out—the very notion of “spheres of influence” is “incompatible with the basic principles of international collaboration.”