Throughout much of 2025, Europe was busy enhancing its defenses against Russia — but just a week into the new year, it finds itself needing to reassess security once more due to President Donald Trump’s threats to annex Greenland.
Trump has intensified his demands for Greenland — a semi-autonomous territory of Denmark — to come under U.S. governance. This week, the White House indicated that Trump was looking at various measures to achieve this, including potential military intervention.
Greenland, the largest island globally, is abundant in untapped mineral wealth. Even though it is geographically part of North America, it is politically associated with Europe.
Securing the island would be a significant challenge. In addition to political hindrances both at home and abroad, any attempt to forcibly take the territory would place the U.S. in opposition to its NATO partners.
Would NATO confront the U.S. over Greenland?
In a CNN interview earlier this week, senior Trump advisor Stephen Miller implied that no European nation would be willing to fight to defend Greenland. While not outright dismissing the notion of U.S. military action in Greenland, he contended that “there’s no need to even think or converse about this in the context of a military operation [because] nobody’s going to engage the United States militarily over Greenland’s fate,” citing the island’s small populace.
Denmark and Greenland, on the other hand, are taking the prospect of U.S. military engagement seriously. On Tuesday evening, Danish Defense Minister and Deputy Prime Minister Troels Lund Poulsen stated that Denmark would allocate 88 billion Danish kroner ($13.8 billion) to rearm Greenland, given “the serious security climate we find ourselves in.”
Notwithstanding Denmark’s apparent commitment to defend Greenland, experts expressed to CNBC their skepticism that European forces would ever engage American troops.
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Edward R. Arnold, a senior research fellow at the Royal United Services Institute for Defense and Security Studies in Britain, shared with CNBC during a call on Tuesday that the White House possesses the military capability to act on Greenland and, if desired, could do so “quite swiftly.”
However, Arnold noted that Washington wouldn’t need to execute an operation like the one seen in Venezuela over the past weekend, stating that “it would be entirely unopposed.”
“What European military leader would fire upon a U.S. troop transport entering Greenland?” he queried. “That would ignite a conflict within NATO, potentially. And the U.S. is aware of that.”
The United States holds, by a significant margin, the greatest military power among NATO countries. In 2024, NATO assessed that the U.S. had 1.3 million military personnel compared to the collective 2.1 million personnel of the rest of the alliance. Turkey had the next largest military force with an estimated 481,000 personnel.
Arnold anticipates that the U.S. will steadily increase the number of troops stationed in Greenland, rather than initiating a full-scale military campaign or invasion.
“They simply wouldn’t engage them,” he remarked regarding NATO forces. “So you have this unusual scenario where the U.S. is placing troops into Greenland, and the Europeans can’t do much about it other than making political protests.”
Georgios Samaras, assistant professor of public policy at King’s College London, concurred that Greenland and the broader NATO alliance would have limited means to prevent a U.S. move to gain further control over the island.
“I don’t see how NATO could deter the U.S. — especially considering we’re addressing a superpower with numerous military bases across the continent that could theoretically be utilized to invade a NATO member from within,” he told CNBC during a call.
In addition to the challenge of turning against one of its own members, NATO would have to consider the wider security ramifications of severing ties with the U.S., as noted by Jamie Shea, an associate fellow in Chatham House’s International Security Program and a former member of NATO’s international staff.
“I would not expect a military reaction [from NATO] as the U.S. would swiftly manage whatever limited forces the Europeans could dispatch, and it’s extremely unlikely that European governments would contemplate doing this,” he told CNBC. “They require all their resources for the defense of Europe and to contribute to a reassurance force for Ukraine.”
The demise of NATO?
On Monday, Danish Prime Minister Mette Frederiksen cautioned that an American takeover of Greenland would signify the end of NATO. Out of NATO’s 32 members, 23 – including Denmark – are also European Union members, which have been working diligently to ensure that Trump’s administration maintains its support for Ukraine.
“They would want to avoid a direct confrontation with the U.S., which would mark the termination of NATO and the U.S.’s backing for Ukraine,” Shea reasoned.
Samaras from King’s College agreed that any escalation regarding Greenland would be detrimental to NATO.
“When a NATO member threatens another alliance member, it doesn’t merely lead to a dispute. It undermines the alliance’s collective defense commitment, rendering it conditional and political,” he stated. “It would effectively mean the end of NATO. I doubt NATO could persist.”
Shea informed CNBC that while European military opposition is improbable, NATO, via the European Union, possesses avenues to apply pressure on Washington.
“Where Europe might exert leverage on the U.S. is economically, should the EU decide to implement sanctions such as tariffs or restrict access for U.S. firms and investments,” Shea explained.
“European nations could also prohibit the U.S. from accessing European military bases or assets like early warning radars. However, these would undoubtedly be challenging decisions for European governments to confront, especially when they’ve been striving to engage Washington on a Ukraine peace initiative and security assurances.”
Trump: U.S. ‘will always support NATO’
Despite his aspirations for Greenland, which may drive a wedge between the U.S. and its NATO partners, Trump asserted on Wednesday that America stands firmly behind the alliance — all while criticizing the organization.
“Recall, for all those enthusiastic NATO supporters, they were at 2% GDP, and most weren’t paying their dues, UNTIL I CAME ALONG,” he remarked in a Truth Social post, referring to member nations’ defense spending targets. Trump further mentioned that the alliance would struggle to mitigate modern security challenges without the U.S. involved.
“RUSSIA AND CHINA FEAR NATO ZERO WITHOUT THE UNITED STATES, AND I DOUBT NATO WOULD SUPPORT US IF WE TRULY NEEDED THEM,” he stated. “We will always support NATO, even if they may not support us.”
