President Donald Trump and others in his administration have dramatically escalated their rhetoric about the strategic importance of Greenland and their desire to seize “ownership” of it, expanding on an issue the president has pursued since his first term in office and even more vociferously this time. Indeed, the Danish and Greenland Home Rule foreign ministers are scheduled to meet with Vice President J.D. Vance and U.S. Secretary of State Marco Rubio in Washington tomorrow to discuss Greenland. On the core point, U.S. officials are right: Greenland is critical to the defense of the United States. Where the administration goes wrong, however, is in how it has approached the issue. Public threats to buy Greenland or even use “military force” are not only unnecessary — they are counterproductive.
I know this not as an academic observation, but from direct experience. From 2003 to 2004, while serving in the U.S. Department of Defense, I played a key role working with the Danish government and the Greenland Home Rule government to upgrade the early-warning radar at Thule Air Base, as it was known before it was renamed Pituffik Space Base in 2023. The radar modernization was essential to supporting the U.S. homeland missile defense mission. Without access to this radar, it would be far more difficult — if not impossible — for the U.S. military to defend the American homeland against long-range missile threats from North Korea or other adversaries.
The strategic importance of Greenland is not a new discovery. The United States has recognized its crucial location for more than eight decades. When Denmark was invaded and occupied by Nazi Germany in 1940, U.S. military forces moved quickly to occupy Greenland to prevent it from falling into German hands. During World War II, Greenland became a vital node in the North Atlantic air ferry route for the U.S. Army Air Force aircraft that transited to Europe. The airfields the United States built in Greenland enabled bombers and other military aircraft to transit to Great Britain, supporting the build-up of U.S. strategic airpower that ultimately help defeat Germany and the Axis powers.
During the Cold War, Greenland assumed an even more central role in U.S. and NATO defense strategy. The 1951 Defense of Greenland Agreement between the United States and Denmark formalized an expansive U.S. military role on the island. In practical terms, the agreement gave the United States wide latitude to do whatever was necessary to defend Greenland — and, by extension, North America, against any threat from the Soviet Union. The treaty is also a pragmatic acknowledgment of reality: Denmark retains sovereignty, but Greenland’s defense rests on a bilateral security commitment in which U.S. military capabilities are decisive.
At its peak, the United States stationed more than 10,000 military personnel in Greenland, supporting nuclear bomber operations, air and missile early warning, and anti-submarine warfare. That presence required the development of extensive infrastructure, much of which still shapes Greenland today. Until very recently, Greenland’s main international airport, for example, was Kangerlussuaq Airport, originally the U.S. Air Force’s Sondrestrom Air Base.
Following the end of the Cold War, the United States closed most of its military installations in Greenland, with one critical exception: the early-warning radar at then-Thule Air Base. That installation remains indispensable to U.S. and allied defense today. It provides essential radar data warning of missile threats from Russia, China, North Korea, and others. In 2004, the radar was significantly upgraded specifically to support the U.S. homeland missile defense mission.
With the return of great-power competition, President Trump is right to highlight Greenland’s strategic value once again (though it does not have, as he asserted, “Russian and Chinese ships all over the place”). Beyond missile warning, Greenland’s geography makes it uniquely important for countering Russian submarine activity in the North Atlantic and Arctic. As undersea competition intensifies, Greenland’s role in maritime domain awareness and anti-submarine operations will only grow.
Counterproductive Approach
But none of that justifies or rationally explains the tactics that Trump and other administration officials are using in what they say is a bid to ensure U.S. security. In fact, the current approach could weaken rather than strengthen U.S. security.
First, Greenlanders themselves are unlikely to want to become part of the United States. As one of the few Americans who has negotiated directly with the Greenland Home Rule government, I can attest that these negotiations are complex and often difficult, even when conducted respectfully and behind closed doors. They require patience, persistence, and a deep understanding of local political realities. Public talk of annexation reflects neither.
Second, annexation rhetoric is politically toxic in Denmark, one of America’s most dependable NATO allies for more than 80 years. Denmark has been a steadfast partner in U.S. and allied defense, including in Greenland, but also in Iraq and Afghanistan, where it lost soldiers in U.S.-led missions. Undermining trust with Copenhagen over sovereignty issues would weaken the very alliance system that underpins U.S. security in the North Atlantic and beyond.
Third, the domestic politics in Greenland between the Home Rule Government and Copenhagen tend to be messy. Were the United States to annex Greenland, it would inherit a history of complicated domestic politics. Under the current arrangement, dealing with Greenland’s domestic political challenges is the responsibility of the Danish government, thus freeing the United States to focus on the key priority: security.
Strategic and Sustainable Security
There is a far better — and more effective — path forward.
The geopolitical and strategic environment in and around Greenland has changed fundamentally since the United States drew down much of its military presence in the early 1990s. The most consequential shift has been the return of sustained great-power competition, particularly with Russia and China, both of which increasingly view the Arctic as a domain of strategic competition rather than peripheral interest. As a result, the assumptions that underpinned earlier U.S. force posture decisions no longer hold. The time has come to reassess whether the current U.S. military posture in Greenland is sufficient to meet today’s — and tomorrow’s — security challenges.
As a first step, the Department of Defense should conduct a comprehensive review of U.S. defense requirements in the North Atlantic and North America. That review should be explicitly cross-domain in nature, integrating missile defense, space-based missile warning and tracking, undersea warfare, Arctic domain awareness, and the protection of critical infrastructure. It should also account for the growing interdependence between space, cyber, and conventional military operations, as well as the increasing importance of early warning and decision-time resilience in a crisis.
Based on this assessment, the United States should consider a series of practical, scalable measures to strengthen security in and around Greenland, including:
- Modernizing and expanding early warning and space-domain capabilities at existing U.S. installations to address emerging missile threats, including advanced cruise and hypersonic systems.
- Enhancing undersea surveillance and maritime domain awareness, recognizing Greenland’s strategic position astride key North Atlantic and Arctic sea lines of communication.
- Improving Arctic infrastructure and resilience, including logistics, communications, and energy systems, to ensure sustained operations in extreme conditions.
- Exploring rotational or presence-based deployments, rather than permanent basing expansions, to increase flexibility while minimizing political friction.
- Deepening intelligence, planning, and operational coordination with Denmark and NATO allies to ensure that Greenland-related contingencies are fully integrated into alliance defense planning.
Critically, any changes to U.S. posture should be pursued in close coordination with Denmark and Greenland. Following the defense review, Washington and Copenhagen should work together to update the 1951 Defense of Greenland Agreement — or its relevant annexes — to reflect modern defense requirements, technological realities, and alliance priorities. A tailored update would provide the legal and political framework necessary to support new capabilities while reaffirming respect for Danish and Greenlandic sovereignty.
This approach offers multiple strategic benefits. It would strengthen U.S. homeland defense, reinforce NATO cohesion, and enhance deterrence in the Arctic without resorting to unnecessary or destabilizing political moves. It would also demonstrate that the United States remains committed to working with allies rather than around them when addressing emerging security challenges.
Greenland is indispensable to the defense of the United States. That has been true since World War II and remains true today. The challenge is not recognition of Greenland’s importance; it is ensuring that security enhancements are strategic, sustainable, and allied-driven. Done correctly, a modernized approach to Greenland’s defense can enhance deterrence, preserve stability in the Arctic, and strengthen the transatlantic partnership for decades to come.
FEATURED IMAGE: A general view of the capital Nuuk, Greenland, on March 4, 2025. US President Donald Trump has strained relations with Denmark by repeatedly signalling that he wants control over Greenland, an autonomous Danish territory. (Photo by ODD ANDERSEN/AFP via Getty Images)
