WASHINGTON DC:  The United States’ capture of Venezuelan President Nicolás Maduro has clearly emboldened President Donald Trump, who has subsequently threatened to unleash the US military on Cuba, Colombia, and, until pulling back this week, Iran. More ominously, he has also raised the prospect of forcibly seizing Greenland, a self-governing territory of Denmark, a longstanding US NATO ally.

Should Trump act on Greenland, the NATO alliance would be shattered, undermining US security and that of the broader West. Worse still, such behavior would normalize territorial predation by great powers, making Chinese action against Taiwan and Russian expansion into the Baltics – and even Central Asia – more likely.

Although Trump frames the takeover of Greenland as a national-security imperative, the US already has a defense agreement with Denmark, maintains a military presence on the island, and enjoys extensive basing rights. It is difficult to foresee what marginal benefits, if any, might be gained from an illegal occupation.

To be sure, it is unclear whether Trump truly intends to act on this rhetoric or is merely bloviating. US Secretary of State Marco Rubio has suggested that Trump’s escalating rhetoric is merely a negotiating tactic meant to pressure Denmark into selling Greenland. If so, it has backfired spectacularly, provoking public outrage in Denmark and Greenland.

Still, no one in Denmark or across Europe should be complacent. Now is the time to strengthen Greenland’s defenses further against Russia and China, thereby undercutting Trump’s stated rationale, and to ensure domestic peace on the island. At the same time, Denmark and its partners should accelerate the development of the island’s mineral and energy resources, mitigating the commercial incentives that appear to drive Trump’s interest in annexation.

At this point, the risk of NATO fracturing is far too great for supporters of the alliance in the US Congress – Democrats and Republicans alike – to remain silent. An impulsive assault on a longstanding ally like Denmark would be catastrophic, prompting Japan, Taiwan, South Korea, Canada, and others to consider alternative security arrangements that reduce their dependence on an untrustworthy US.

Trump’s threats also jeopardize America’s economic prospects. Denmark and the rest of the European Union are indispensable partners in any realistic US growth strategy in the face of China’s rise. The EU’s consumer markets, manufacturing base, supply chains, and research ecosystems are critical to advances in AI, quantum computing, clean and fusion energy, and the life sciences. Alienating Europe would undermine virtually every sector of the US economy.

More than one billion affluent consumers across North America, Europe, Japan, South Korea, and other parts of Asia – linked by a long history of successful, if sometimes rocky, economic partnerships – represent the strongest foundation for long-term prosperity. Add India, which has been moving closer to the US and its allies as a counterweight to China, and the result would be an almost unbeatable alliance.

Trump’s boneheaded imperialism threatens to torch that future, and Republicans who oppose him, like Senator Mitch McConnell, must join Democrats in speaking up. They should say that Trump is wrong to coerce Denmark, and that if he does seize Greenland, the US will give it up once Trump leaves office. This gets at the weakness in Trump’s promise of riches – it will take decades to realize profits – and meets a need now. US allies are already losing faith, and unless they see clear opposition, they will assume that silence means consent to Trump’s land grabs. Acting on that assumption, allies will hedge, deepening ties with China and other rising powers to counterbalance an increasingly rogue US administration.

If that happens, the next administration will struggle to restore trust. Even if the Democrats retake the White House in 2028, US partners will continue to worry about the potential return of Trumpism in 2032. With no realistic chance of rebuilding the multilateral order, the next administration will be forced to operate from the wreckage Trump leaves behind.

Trump’s foreign adventurism underscores his overreach, corruption, and willingness to accommodate kleptocratic and autocratic regimes. Some may counsel patience, urging a wait-and-see approach to determine whether Trump’s gambits yield strategic benefits. That would be a mistake. Hesitation only signals indecision and invites further damage. The current moment demands a clear rejection of imperialist land grabs.

Commercial motivations matter as well. Trump’s foreign-policy initiatives often focus on creating private business opportunities that benefit him personally, with his plan to use taxpayer funds to subsidize oil companies in Venezuela being a prime example. Trump’s opponents should emphasize the prospect of future congressional investigations, regulatory scrutiny, sanctions, and criminal prosecution for those tempted to participate in such schemes.

Robber barons and imperialism go hand in hand. In trying to remake US foreign policy in his own image, Trump is reviving an international order defined by brute force, in which powerful countries seize territory so that their leaders can enrich themselves.

While that approach serves Trump’s personal interests, it is a losing strategy for the US. Some Republicans may be willing to break NATO, but Democratic leaders who hope to govern again must speak clearly now or risk inheriting a world in which the foundations of American prosperity and security have already been damaged beyond repair.

James C. O’Brien was US Assistant Secretary of State for Europe and Eurasian Affairs during the Biden administration.

 Copyright: Project Syndicate, 2026.
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