Can the US already set up whatever military presence they want on Greenland through an agreement with Denmark signed long ago?
Executive summary
The short answer: no — the 1951 U.S.–Denmark defense agreement gives Washington sweeping operational rights in Greenland but does not lawlessly permit the United States to “set up whatever military presence they want” without Danish (and now Greenlandic) involvement and political negotiation. The treaty grants broad rights to construct, operate and move forces across Greenland under a NATO framework [1] [2], but Danish sovereignty and post‑2004 rules giving Greenland a formal consultative role constrain unilateral American action in practice [1] [3].
1. What the Cold War pact actually authorizes
The written 1951 agreement explicitly authorizes the U.S. “to improve and generally to fit” designated defense areas, to construct and operate bases, and to enjoy free access and movement for ships, aircraft and armed forces within those defense areas and adjacent airspace and waters (Avalon Project text) — language that gives the United States wide operational leeway born of Cold War imperatives [1] [2]. That is why analysts say the accord allowed a U.S. presence far beyond World War II levels and why Pituffik (Thule) evolved into a permanent early‑warning and space operations hub [2] [4].
2. Why “wide operational leeway” isn’t the same as carte blanche
The agreement is careful to state that these rights are “without prejudice to the sovereignty of the Kingdom of Denmark” and that U.S. activities are to be exercised in coordination with Danish authorities — a legal reservation that preserves Danish control even while permitting extensive U.S. use [1]. Contemporary reporting and diplomats note that, although the treaty makes it easier for the U.S. to increase forces for defense reasons, doing so still requires negotiation with Copenhagen and, politically, with Greenland’s authorities and the NATO framework that underpinned the original deal [2] [5] [6].
3. Newer political and consultative limits: the 2004 and Greenlandic angle
The post‑Cold War legal and political landscape matters: the 1951 text was updated in later practices and in 2004 Greenland’s semiautonomous government gained formal recognition in consultations about military changes, meaning the U.S. “must inform Denmark and Greenland of any proposed changes” — a practical constraint on unilateral expansion [3]. Danish and Greenlandic leaders publicly reject any suggestion of sale or forcible seizure of Greenland, and Copenhagen has emphasized coordination with Greenland’s government for any increased foreign military footprint [7] [8].
4. How officials and journalists frame the tension
Some outlets and officials emphasize the treaty’s breadth, saying the U.S. “could bring as many troops as it wants” under existing arrangements, a characterization used to underscore how legally permissive the Cold War pact appears [9] [5]. Others — including Danish ministers and NATO diplomats quoted in reporting — counter that political, consultative and sovereignty constraints make the idea of unilateral U.S. occupation unrealistic and diplomatically explosive, prompting allied reconnaissance missions and expanded NATO cooperation instead of any unilateral seizure [10] [8].
5. Bottom line: legal muscle plus political leash
Legally, the 1951 agreement furnishes the United States with substantial rights to maintain and expand military facilities in Greenland and to move forces in support of NATO‑defined defense needs [1] [2]. Politically and practically, however, those rights operate inside a leash: Denmark’s sovereignty remains explicit in the treaty, Greenland’s consultative role after 2004 narrows unilateral options, and the reputational and alliance costs of attempting forcible, unilateral expansion would be profound — which is why contemporary diplomatic and press accounts describe the pact as enabling but not an automatic blank check for “whatever” presence the U.S. might desire [1] [3] [6].