In October 2024, only a month before the U.S. presidential election, one of the rising stars in Washington’s national security apparatus paid a visit to Brussels. Speaking to a sold-out audience at the Royal Library of Belgium, the strategist laid out his theory of geopolitics to a crowd full of European Union officials, academics and journalists. He said that China is the United States’ biggest threat, and Europe must learn to defend itself.
The national security analyst was Elbridge Colby, a principal driver of Washington’s Euroskeptic turn during President Donald Trump’s second term and a figure key to understanding fraying transatlantic ties. Colby views the EU not as an ally bound to the U.S. by shared history and values, but instead as a vehicle for Washington’s interests and a roadblock to the U.S.’s pivot to Asia — or, in a worst case scenario, even as a possible continental hegemon that could deny the U.S. access to European markets and military bases.
Colby’s worldview centers on economic might, military power, state interest and great power conflict, and is guided by the view that the U.S. must deny to other states hegemonic control over key regions of the world. As part of that perspective, China must be denied Asia. That logic also means, as he wrote in his 2021 book The Strategy of Denial, that the EU must be denied state-like control over Europe, too.
His ideas hold sway in Trump’s Washington. Colby, the Pentagon’s policy chief, helped to shape the U.S. National Security Strategy in December, which laid out a confrontational policy with the EU and was behind a halt in weapons shipments to Ukraine last year. In May, Alexander Velez-Green, one of Colby’s proteges in the Pentagon told NATO allies in Brussels that the U.S. would continue to pull military assets from Europe.
“The European Union, in many ways, has strayed from its original purpose,” said Wess Mitchell, a former colleague of Colby’s who served in the first Trump administration. “U.S. policy should be based on the actions that the European Union takes, whether it’s economically or otherwise vis-avis the U.S. and our chief interests, rather than being based on nostalgia or some kind of gauzy transatlantic spirit.”
An American realist rising
Colby, who declined an interview request via the Pentagon, has long had an approach defined by realism, viewing global politics as a competitive struggle for power in which states have clear interests and should deny their opponents control over key regions of the world — realpolitik for the 21st century. That’s opposed to a liberal approach which centers on the rule of law, or a constructivist approach that celebrates shared norms and ideas.
Former colleagues say he’s known to like the phrase ‘speak softly and carry a big stick,’ a proverb popularized by Teddy Roosevelt. Before taking on his current role at the Pentagon, he had a prolific presence on social media where he often laid out punchy arguments supporting Trump’s foreign policy positions and frequented MAGA-aligned podcasts like Tucker Carlson’s show. He goes by the nickname “Bridge,” and European strategists who have spoken with him call him a “true deliberative intellectual” willing to get into long, heady debates about geostrategic issues.
Colby’s geopolitical approach has become more popular in Washington in recent years. His former colleague Mitchell is a principal at the Washington-based geostrategy think tank Marathon Initiative, which he co-founded with Colby in 2019, and a former assistant secretary of state in the first Trump administration. The two got to know each other around 2010. At the time, conservative foreign policy thinkers were typically still wrapped up in a neoconservative approach that focused on the threat of terrorism and the Middle East.
That’s not how the two of them saw the world. It was China and to a lesser extent Russia — not the Middle East and Afghanistan — that posed the greatest threats to the U.S.
“Bridge is a serious strategist who developed a clear and compelling framework for repositioning U.S. strategy to deal with the central problem of our time, which is the growth of Chinese power,” said Mitchell.
Peter Rough, a senior fellow at the Hudson Institute, a conservative think tank in Washington D.C., knows Colby and argued that he considers himself a “realist grounded in a proper understanding of the limits of U.S. power shorn of liberal pretense.” In that world, tough choices have to be made. Colby believes that Washington can’t both protect Europe and deny China’s rise in Asia.
“He is one of the most eloquent proponents of that worldview, which also explains why he holds such an important position at DoD,” said Rough.
Colby’s strand of realism propelled him into the first Trump administration, where he served under the president’s then secretary of defense, Jim Mattis. After starting the Marathon Initiative with Mitchell in 2019, he returned in the second Trump White House as the third-highest-ranking official in the Pentagon.
However, his realist worldview has led to shifting policy prescriptions between support for and against a muscular American military presence in Europe. As late as 2016, Colby had backed continuing American military support in the Baltics to repel a Russian threat. But a decade later, his approach has changed drastically. In a 2023 piece for Time magazine, he said that “However just and noble Ukraine’s cause is, continuing to focus on it at the expense of confronting and deterring China is not wise, moral, or conservative.”
Last year, he was behind a sudden halt in weapons shipments to Ukraine.
But that doesn’t mean Colby-style realism and laser-eyed focus on China has become the only thread in Trump’s foreign policy playbook. Aside from his preference to pull away from Europe to prioritize China, there’s also a group determined to export MAGA-style culture war politics to Europe’s far right.
While the culture war drove Trump’s rise to power, Colby came up in Washington largely through policy circles, rather than political ones. The culture war school emphasizes Europe’s leftist, “woke” characteristics, rather than the strategic interests that animate Colby, according to Leonard Schuette, a German national and research fellow at Harvard’s Kennedy School. That approach is practiced by Trump’s aide Stephen Miller, Vice President J.D. Vance and Trump himself. At times, that’s led to tensions in Washington, pitting strategic realists like Colby against MAGA culture warriors like Miller.
Nowhere is this strain clearer than in the NSS, which received input from MAGA foreign policy thinkers from across the spectrum. The strategy was not a pure Colby document, according to Wannes Verstraete, an associate fellow at the Egmont Institute in Brussels. For example, it emphasized the Western Hemisphere, as opposed to prioritizing only China.
At the same time, Washington’s recent war in Iran also runs directly counter to Colby’s preferred approach, which would emphasize a more hawkish position on China and a continued pullback of American troops from Europe.
At the highest levels, Colby may be losing some of the key global foreign policy arguments in Washington, even as he wins on Europe, according to strategists.
Even so, Europeans have chased after Colby in recent years, recognizing his importance to Trump’s foreign policy toward Europe, in particular, and his ability to steer longer-term shifts in policy, such as troop deployments. European foreign policy strategists said that getting a meeting with him was highly desirable in the run-up to the 2024 elections, as they tried to get a sense of how a second Trump administration would approach the transatlantic relationship.
“It was clear he was rising in the ranks,” one European national security thinker who met Colby said.
Europe as a hegemonic threat to the U.S.
The implications of Colby’s thinking are far more sweeping than limited shifts to the U.S.’s military assets in Europe. In December, the EU’s defense commissioner, Andrius Kubilius, took to his personal blog to address the latest NSS. That document, read with shock in European capitals, had laid out a combative and coercive anti-EU approach to America’s role in Europe.
But in the strategy, Kubilius saw longer-term tactical motivations, not merely the nationalist, anti-EU attitude of Trump. The “antagonistic language on the European Union,” he wrote, “comes not from American sentimental emotions about ‘good old Europe,’ but from deep strategic considerations… EU unity is against USA interests.” Those strategic considerations, Kubilius argued, were laid out plain for all to see in Colby’s 2021 book, The Strategy of Denial.
It’s not the first time that Kubilius has interacted with Colby’s work. Aside from the blog post, Kubulius has a signed copy of Colby’s recent book on his desk and has met twice with the American, according to his office.
The book argues that U.S. foreign policy should deny any state hegemonic control over one of the great economic and military centers of the world, such as Asia, Europe, North America and to a lesser extent, the Persian Gulf. If single states were to control one of these centers, it would create an imbalance of power, threatening U.S. security.
In Europe, Colby contends, Russia has long aspired to dominance on the continent but now is “almost certainly incapable of mounting a serious bid for regional hegemony” — a claim that hasn’t aged well, in light of Russia’s full-scale invasion of Ukraine in 2022. That makes the EU, in Colby’s view, the most likely hegemon on the continent.
“The most plausible alternative to Russia as an aspiring hegemon in Europe is likely the European Union, or a more cohesive entity emerging from it,” he writes. “Although a loose coalition of states is unlikely to be able to seize and hold hegemony because of its inherent fractiousness, a unifying superstate could.”
For this very reason, “the United States is therefore better off if Europe is not a highly unified superstate,” he writes. Still, he acknowledges that a confederated Europe to some degree could benefit Washington, such as by creating a unified front against China. However, he writes that “this does not mean the United States would benefit if the European Union or a successor became a truly unified entity capable of establishing regional hegemony and unduly burdening or even excluding U.S. trade and engagement.”
Colby’s boss has echoed that analysis of the EU. “The European Union was formed in order to screw the United States,” Trump told reporters in February 2025.
Kubilius jumped on Colby’s line of thinking in his December blog post, arguing that it explained at a deep strategic level the entire shift in the U.S.’s position to the EU. “Americans are planning to fight against the European Union, against our strength through unity, since in their vision the European Union can become a threatening [sic] to American interests — a unifying superstate,” wrote Kubilius.
It’s a stunning but not baseless accusation from the EU’s defense commissioner . Indeed, an increasing number of current and former American officials have expressed concern about the EU denying the U.S. free access to the bloc’s markets and American military bases on European territory.
As Colby’s former colleague Mitchell said, “I see a number of areas where EU policies... are not in the American interest.” For example, Mitchell noted that EU legacy trade practices are grounded in a lack of reciprocity that hinders America’s ability to reindustrialize to face the China threat, and that its tech regulations impair U.S. firms’ ability to develop the innovations that the U.S. will need to maintain strategic superiority in any future war with China. In retaliation, however, the U.S. has slapped higher tariffs on EU goods as part of the Turnberry trade deal first reached between the two sides last summer.
After a trip to Brussels last December, U.S. Deputy Secretary of State Christopher Landau wrote on X that EU countries “pursue all sorts of agendas that are often utterly adverse to U.S. interests and security.” After Spain and Italy denied the U.S. access to certain military bases during the U.S. and Isarel’s war in Iran, Secretary of State Marco Rubio called lack of access “a problem” that needed “to be examined.”
But what about Colby’s concern that Europe could actually form a unified superstate?
Rough is highly skeptical of the idea, saying that it’s unlikely Europe can federalize if under pressure from the U.S. and China, unless Germany takes a leading role. Schuette said that a European federal union was still an unrealistic proposition. Even so, the EU had grown economically powerful enough that he said, “dividing the EU is still in the American interest.” Trump has already attempted to do that by trying to strengthen bilateral relations with far-right movements in EU member states, including Hungary or Poland, rather than deal with the EU as a whole.
For his part, Colby has also been dismissive toward European attempts to build a more unified and geopolitically capable Europe. In response to French President Emmanuel Macron’s “Europe speech” in 2024 which called for a stronger role for a unified Europe in global politics, Colby told Politico that “if Europe is going to be some kind of third pole, then why would we help you become that?” To Colby, a realist position toward Europe isn’t only about military burden-sharing, but also about containing the bloc’s geopolitical ambitions.
That’s one of a string of contradictions in his geopolitical worldview. Colby’s been one of the strongest advocates for a more muscular European military presence to free up U.S. resources, but he’s also concerned about the risks a more unified Europe could pose to the U.S., according to his own writing in The Strategy of Denial.
Another paradox is China, which he wants to contain. Schuette said it was a “tragedy” that the current administration had not tried to create a transatlantic alliance against China in trade. “Europeans have perhaps never been more aware of China’s economic coercive practices,” he said.
Europe’s response to American realism
For some European strategists, Colby’s clarity, the naked anti-EU language in the NSS and more recent moves like Trump’s designs on Greenland are definitive signals of how the EU needs to adapt. “I’m sensing this time around more evidence that European leaders understand that Trump is hostile to Europe,” said Schuette, the European strategist, in the context of Trump’s designs on Greenland in January and potential future U.S. aggression toward Europe. “This is clearly going to happen again.”
In that realist world, building up the EU’s tools to deal with great power conflict is pivotal, Schuette said, such as rapidly increasing Europe’s defense capacities, de-risking from the transatlantic dependency in technology and pursuing a more robust Europeanized command and control infrastructure. That’s something Kubilius has called for as well, including by proposing a European Security Council.
More elected officials are also getting on board with that agenda. MEP Sophie Wilmès (Renew, BE), a former Belgian prime minister, said that the NSS signaled that America’s goal was “the dismantling of the European Union, nothing more, nothing less,” and that the European Council needed to move to more qualified majority voting in decision-making to be more “proactive and responsive” in geopolitics.
However, there’s an irony at the heart of Washington’s transatlantic policy.
In February in Brussels, Colby told NATO defense ministers that “there is nothing anti-European” about asking Europe to increase its defense capacities to repel Russia. “To the contrary,” he said, “it reflects hope and indeed confidence in Europe’s capacity to act.” The unaddressed paradox is that Washington pushing the EU to stand on its own two feet militarily may accelerate the very political consolidation that Colby fears is counter to U.S. interests.
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