The recent trilateral agreement reached by the United States, Denmark, and Greenland holds significance far beyond just expanding American access in the Arctic region.
This agreement establishes military rights, limits the establishment of footholds by competitors, and plans for a potential future independence of Greenland, aiming to address vulnerabilities that the US previously faced in countries such as Djibouti in East Africa and Diego Garcia in the Indian Ocean. This move is expected to significantly limit Russia and China’s maneuvering space.
In 2017, when the Chinese regime established its first overseas military base in Djibouti, the US already had a solid presence just a few miles away at Camp Lemonnier. Washington not only negotiated the rights to use the base (valid until 2034) but also invested heavily in its development, seeing Djibouti as a long-term military hub in Africa.
However, this did not prevent Beijing from reaching defense agreements, investing in nearby port infrastructure, and building military facilities. This situation highlights an unsettling lesson: having secured rights to a base does not mean that adversaries will be completely kept at bay.
The situation at Diego Garcia Island presents another cautionary tale. The base has been operational for decades, holding irreplaceable strategic importance for the US and the UK. However, sovereignty disputes surrounding the Chagos Archipelago ultimately led to negotiations between London and the East African nation of Mauritius regarding the legal framework of the base’s future.
A treaty in 2025 attempted to recognize Mauritius’ sovereignty while ensuring the UK had operational rights for 99 years, yet the arrangement has not been finalized to date.
Given these past experiences, the new trilateral agreement between the US, Denmark, and Greenland takes on even greater significance. It not only expands American access in the Arctic but also aims to proactively address external issues that have complicated arrangements in Djibouti and Diego Garcia.
China seized opportunities within this context. A Chinese state-owned enterprise acquired a 23.5% stake in Djibouti’s port, while a Chinese military base was established near the Doraleh Multipurpose Port.
Events in Djibouti illustrate a strategic vulnerability that the Greenland agreement now aims to address: allowing host governments to respect US base rights while permitting competitors to develop infrastructure nearby.
In contrast, the situation at Diego Garcia Island presents a different scenario. After decades of legal and political disputes over British sovereignty, the unresolved issue of continued base usage became intertwined with broader Chagos Islands ownership questions. In May 2025, the UK and Mauritius signed a treaty where the UK recognized Mauritius’ sovereignty but retained jurisdiction over Diego Garcia, initially for 99 years with the possibility of extensions.
This treaty includes substantive safeguards like restricting foreign security forces’ activities and developments around the base. However, over a year later, the implementation of the treaty remains incomplete.
Therefore, the case of Diego Garcia Island, rather than a tale of failed base construction, illustrates the strategic costs of unresolved political foundations.
The US can modernize and expand the Pituffik Space Base on Greenland, establish new defense zones in Narsarsuaq and Mestersvig, and potentially agree to additional locations through consultation.
American aircraft have broad rights to fly over and land throughout Greenland, while US government vessels have rights to operate in Greenland’s territorial waters (unless otherwise agreed upon).
Furthermore, the agreement explicitly links the US’s access rights with the construction of the “Golden Dome” homeland defense system.
However, these are just the visible military outcomes. The agreement prohibits any non-NATO country from establishing manned or unmanned military facilities or maintaining long-term military presence unless otherwise agreed upon, closing the loophole China previously exploited in Djibouti.
The agreement effectively addresses the risk of acquiring strategic influence through commercial means. In sectors involving national security or public order, the agreement allows blocking investors from outside NATO, NATO partner countries, or the European Union (EU) from gaining control, exerting significant influence, or obtaining sensitive non-public information.
Russia’s challenge lies in geography rather than investments. Moscow already possesses Arctic territories, military infrastructure lacking in China, and the Northern Fleet.
Greenland cannot eliminate these geographical advantages. Instead, it can help enhance control over western passages — vital routes for Russian aircraft, submarines, and ships moving towards North America and the North Atlantic.
The agreement requires NATO to strengthen planning, troop deployment, military exercises, and joint intelligence collection in the Arctic region. Denmark also pledges to enhance its own land, sea, air, and space military posture. The US’s broader access in Greenland ensures a more interconnected Northern defense structure, rather than isolated base deployment arrangements.
The agreement has no expiration date to avoid a repeat of the Diego Garcia base situation. Any revisions must be agreed upon by both parties. Importantly, if Greenland exercises its independence, Denmark and Greenland commit to ensuring Greenland remains in NATO post-independence and assumes existing defense obligations under the agreement.
However, there are still limitations. Greenland retains sovereignty protection and self-determination. Any additional US defense areas outside designated ranges will require separate negotiations, and the terms regarding foreign investments do not completely prohibit Chinese business operations. The agreement will only enter into force after Denmark and Greenland complete parliamentary procedures.
The Djibouti situation demonstrates that US security leases and Chinese military bases can coexist. The example of Diego Garcia Island shows how unresolved sovereignty issues can eventually affect the future of the most valuable military facilities.
The Greenland agreement expands US military access, restricts adversary military presence, and scrutinizes strategically sensitive investments. It strengthens NATO integration while countering espionage activities in the defense sector. Even in Greenland’s potential independence, the agreement aims to preserve these arrangements.
These measures do not exclude Russia from the Arctic or stop China from seeking influence in the region through Russia, shipping, science, or commercial activities. Instead, they play a more practical role by making it harder for Russia and China to exploit one of the Arctic’s key strategic geographical features.
In this way, the trilateral agreement protects American economic and financial resources, upholds long-standing diplomatic investments between the US and several NATO allies. Ultimately, it strengthens Western military posture in this vulnerable region.