Greenland Defense Agreement (1951): U.S. Military Rights Explained
Introduction
The Greenland Defense Agreement is a bilateral treaty signed by the United States and Denmark on April 27, 1951, that provides a principal legal basis for American military activities in Greenland within the North Atlantic Treaty Organization (NATO) defense framework. It authorizes the establishment and operation of mutually agreed defense areas, permits military facilities and personnel, and grants specified access and movement rights. These extensive powers do not transfer territorial sovereignty: the agreement expressly preserves Denmark’s sovereignty over Greenland (United States and Denmark, 1951, Articles II and V).
The treaty developed from military cooperation established during the Second World War. An earlier agreement, signed on April 9, 1941, permitted the United States to establish and operate facilities for Greenland’s defense. Following NATO’s establishment in 1949, Denmark and the United States negotiated new arrangements connecting their responsibilities in Greenland with the alliance’s collective-defense plans. The 1951 agreement entered into force on June 8, 1951, replacing the wartime instrument and establishing a continuing basis for military cooperation (United States and Denmark, 1941; United States and Denmark, 1951, Preamble and Articles I, XII and XIV).
American rights under the treaty extend beyond the operation of military bases. Its provisions govern movement through Greenland, the construction and use of installations, relations with Danish authorities, and the legal position of military personnel. The agreement also addresses jurisdiction and the ownership and disposal of military property. The extent of American authority depends on the particular right being exercised and the conditions attached to it, including requirements for mutual agreement on the designation of defense areas (United States and Denmark, 1951, Articles II and V–XI).
The legal arrangements were subsequently modified by the Igaliku Agreement of August 6, 2004. The amendment identified Thule Air Base as Greenland’s only defense area at that time while retaining the procedure for establishing additional areas. It also confirmed the application of the NATO Status of Forces Agreement, superseded the original treaty’s Article VIII jurisdictional provisions, and established consultation arrangements involving Greenland’s Home Rule Government. The resulting arrangements preserve the original defense relationship while giving Greenlandic authorities an expressly recognized role in consultations concerning significant changes to American military operations and facilities (United States and Denmark, 2004, Articles 1–3).
1. From the 1941 Agreement to the 1951 Defense Treaty
Greenland's geographical position made it important to transatlantic aviation, meteorological observation, and the defense of the North Atlantic during the Second World War. Germany's occupation of Denmark on April 9, 1940, prevented the Danish government from exercising its authority over Greenland in the ordinary manner. The United States feared that the territory could become a base for hostile military operations against North America and considered its defense essential to the security of the Western Hemisphere (United States and Denmark, 1941, Preamble).
On April 9, 1941, U.S. Secretary of State Cordell Hull and Henrik Kauffmann, Denmark's minister in Washington, signed an agreement concerning Greenland's defense. Kauffmann acted without authorization from the Danish government in occupied Copenhagen, which rejected the agreement and ordered his recall. The United States nevertheless continued to recognize him as Denmark's diplomatic representative. After Denmark's liberation, both chambers of the Danish Parliament approved the agreement on May 16, 1945, followed by formal royal approval on May 23 (Kauffmann, 25 May 1945).
The wartime agreement recognized Danish sovereignty while authorizing the United States to establish and operate military facilities in Greenland. Articles II and III permitted the construction of landing fields, seaplane facilities, radio and meteorological installations, roads, harbors, and other infrastructure required for defense operations. Article V also granted the United States the right to use and lease necessary areas of land and water. American forces could begin using an area before the precise terms of a formal lease had been negotiated (United States and Denmark, 1941, Articles I–V).
Formal leasing arrangements were not immediately completed for every defense area. An exchange of notes in September 1944 postponed the negotiation of leases until a free Danish government had been established. Denmark subsequently waived remuneration for the wartime use of the defense areas. These arrangements allowed military operations to continue while leaving certain property and administrative questions for later negotiations (Kauffmann, 11 October 1945).
The end of the war did not eliminate Greenland's importance to American defense planning. Military aviation and the territory's position between North America and Europe sustained interest in its airfields, communications facilities, and other installations. Denmark sought to reconsider the exceptional wartime arrangements, while the United States wished to retain access to facilities considered necessary for its security. The establishment of the North Atlantic Treaty Organization in 1949 provided a new institutional setting for negotiating their military relationship.
NATO requested that Denmark and the United States negotiate arrangements allowing the armed forces of member states to use facilities in Greenland for the defense of the territory and the wider North Atlantic Treaty area. The resulting agreement was signed in Copenhagen on April 27, 1951, and entered into force on June 8, 1951, following notification of its approval by the Danish Parliament (United States and Denmark, 1951, Preamble and Article XIV).
Article XII expressly terminated the 1941 agreement upon the entry into force of the new treaty. The 1951 instrument introduced a different legal arrangement: defense areas would be designated by mutual agreement, responsibility for their operation would be allocated between the two governments, and facilities could be made available to other NATO members. Its duration was also linked to the North Atlantic Treaty, replacing the wartime agreement's termination arrangements with a continuing framework for collective defense (United States and Denmark, 1951, Articles II–IV, XII and XIV).
2. Defense Areas and U.S. Military Rights
Article II establishes the principal mechanism through which the United States may establish and operate military facilities in Greenland. It provides for defense areas considered necessary under NATO defense plans, particularly where Denmark cannot establish and operate the required facilities independently. The selection of those areas depends on agreement between the two governments, as does the allocation of responsibility for their operation and maintenance (United States and Denmark, 1951, Article II).
The agreement distinguishes areas operated by American forces from those administered by Denmark. In each case, the government responsible for an area retains the principal operational role, while the other may participate in defense activities under the treaty's provisions. American authority is particularly extensive in areas assigned to U.S. operation, encompassing military construction, personnel accommodation, internal security, and the regulation of military movements.
These rights are governed by the terms of the agreement. The designation of a defense area and the military activities subsequently undertaken within it are legally distinct, and the powers granted to American authorities do not displace Denmark's sovereignty over the territory.
2.1 Establishing and Designating Defense Areas
Article II requires Denmark and the United States to agree on the defense areas necessary for the defense of Greenland and the wider North Atlantic Treaty area. Their selection is based on NATO defense plans and the facilities that Denmark is unable to establish and operate alone. The provision establishes a bilateral procedure for determining where the United States may undertake the military activities contemplated by the treaty.
Once an area has been selected, Article II(2) requires the governments to determine responsibility for its operation and maintenance by agreement in each case. Responsibility may be assigned to either government. The treaty accordingly establishes different arrangements for American-operated and Danish-operated areas rather than placing every military installation under a single system of administration.
The national flags of both countries are to fly over defense areas under Article II(1). This requirement reflects the bilateral character of the arrangements and accompanies the treaty's separate provisions concerning operational responsibility and Danish sovereignty. It does not determine which government commands the forces stationed at a particular installation.
The designation of an area establishes the geographical location to which the relevant military rights apply. Where operational responsibility is assigned to the United States, Article II(3) permits extensive construction and other military activities within that area. The existence of those powers does not independently authorize the designation of additional defense areas outside the agreed locations.
The 2004 Igaliku Agreement retained this distinction. Article 1 identified Thule Air Base as Greenland's only defense area at the time of the amendment while expressly preserving Article II's application to the establishment of new areas. The amendment also provided for the flags of Denmark, Greenland, and the United States to fly over the base, reflecting Greenland's participation in the revised arrangements (United States and Denmark, 2004, Article 1).
2.2 Military Facilities and Operational Control
Where the United States assumes responsibility for a defense area, Article II(3)(b) grants it extensive authority to develop and maintain military infrastructure. American forces may improve the area for military use, construct and operate installations, maintain equipment, and store supplies. These powers expressly encompass meteorological and communications facilities, which support both military operations and the transportation requirements associated with Greenland's geographical position.
The same provision authorizes the stationing and accommodation of personnel, including facilities for their health, recreation, and welfare. American authorities may maintain postal facilities and commissary stores, provide internal security, and undertake measures necessary for the protection of the area. These powers extend to the operation of military installations rather than conferring general governmental authority over Greenland (United States and Denmark, 1951, Article II(3)(b)).
Operational control also extends to specified activities within the defense area and adjacent airspace and waters. The United States may regulate landings, takeoffs, anchorages, moorings, and the movements of ships, aircraft, watercraft, and vehicles. It may improve harbors, channels, entrances, and anchorages. The treaty requires these activities to be conducted with due respect for Denmark's responsibilities concerning shipping and aviation.
Denmark retains a role in the administration of American-operated areas. Under Article II(3)(a), the Danish Commander-in-Chief of Greenland may attach Danish military personnel to the staff of the American commanding officer. The U.S. commander must consult the designated Danish officer on important local questions affecting Danish interests. This arrangement provides for military consultation without transferring command of American forces to the Danish liaison officer.
Article II(3)(c) separately reserves Denmark's right to use U.S.-operated defense areas for the defense of Greenland and the wider North Atlantic Treaty area. Danish authorities may construct facilities and conduct activities there in cooperation with the United States, provided they do not impede American operations.
A corresponding arrangement applies where Denmark assumes responsibility for a defense area. Article II(4) permits American military personnel to participate in the commanding officer's staff and authorizes American use and construction activities that do not impede Danish operations. The treaty thus accommodates different allocations of operational responsibility while preserving the agreed military functions of each area (United States and Denmark, 1951, Article II(3)–(4)).
3. Military Access Beyond Designated Defense Areas
Article V(3) grants American public vessels, aircraft, armed forces, and vehicles rights of access to and movement between defense areas through Greenland, including its territorial waters. These rights encompass movement by land, air, and sea. They were designed to permit military personnel and equipment to reach and operate the installations established under the treaty without requiring a separate authorization for every movement between defense areas (United States and Denmark, 1951, Article V(3)).
The exercise of these rights is governed by general rules mutually agreed upon by the two governments and issued by the appropriate Danish authority in Greenland. Article V(3) also provides freedom from compulsory pilotage and from light or harbor dues. These privileges facilitate military transportation while preserving the agreed conditions under which the access rights are exercised.
American aircraft receive a broader express permission. Article V(3) allows them to fly over and land throughout Greenland, subject to restrictions mutually agreed upon by the governments. The provision also addresses Greenland's territorial waters. Its geographical scope is wider than the boundaries of individual defense areas, although the establishment of permanent military installations remains governed by the separate procedure in Article II.
Article IV extends the defense arrangements to other NATO members. It provides that defense areas are to be made available, so far as practicable, to vessels, aircraft, and armed forces belonging to other parties to the North Atlantic Treaty. Their access is connected to activities for the defense of Greenland and the wider treaty area. The provision does not assign the operation of those facilities to NATO as an institution (United States and Denmark, 1951, Article IV).
Article III established a particular arrangement for Grønnedal, where the operation of the American naval station was to be transferred to Denmark as soon as practicable. The original treaty preserved access for American forces and, where required under NATO plans, forces of other member states. It also contemplated the possibility of Grønnedal becoming a defense area under Article II if Denmark could no longer perform the necessary activities independently. These provisions concerned the original arrangements for that station; they do not establish Grønnedal as a separate defense area under the designation subsequently adopted in 2004 (United States and Denmark, 1951, Article III; United States and Denmark, 2004, Article 1).
The reduction of designated defense areas changed the geographical operation of the treaty without eliminating its general access provisions. Article 1 of the Igaliku Agreement identified Thule Air Base as the only defense area in Greenland in 2004. Article V(3) must consequently be read in conjunction with that designation and the continuing procedure for establishing additional areas. Movement rights do not themselves create new defense areas or confer unrestricted authority to construct permanent facilities elsewhere.
The 2004 amendment also addressed military aircraft landings outside airports. Article 3(1)(b) provides that, in exceptional cases of planned landings, the United States consults with and informs the Danish government, including Greenland's Home Rule Government, to ensure appropriate protection of the environment and hunting areas. Article 3(1)(c) establishes consultation and notification before significant changes to American military operations or facilities. These requirements supplement the original access arrangements without establishing a general Greenlandic veto over military movements (United States and Denmark, 2004, Article 3).
4. Danish Sovereignty and the Limits of American Authority
Article II(3)(b) expressly preserves Danish sovereignty over defense areas assigned to American operation and maintenance. It also recognizes the right of competent Danish authorities to move freely throughout Greenland. The United States may exercise extensive military powers within agreed areas, but those powers derive from the treaty rather than from territorial ownership (United States and Denmark, 1951, Article II(3)(b)).
The distinction is significant because military installations may involve considerable control over access, personnel, infrastructure, and surrounding airspace or waters. Such control concerns the exercise of particular rights granted by Denmark. It does not confer sovereign authority over the territory or extinguish Denmark's legal position as the territorial state.
Denmark's continuing authority is reflected in the treaty's arrangements for military cooperation. Article II(3)(a) provides for Danish military representation within the staff of an American-operated defense area, while Article II(3)(c) reserves Denmark's right to use that area for collective-defense purposes. The right of competent Danish authorities to move throughout Greenland further distinguishes the treaty's operational arrangements from a transfer of territorial sovereignty.
Article XI addresses ownership of military property. Property supplied by the United States and located in Greenland remains American property. The provision also permits the United States to remove removable improvements, facilities, equipment, materials, supplies, and other goods that it has brought into Greenland. Alternatively, such property may be disposed of in Greenland after consultation with Danish authorities (United States and Denmark, 1951, Article XI).
These removal and disposal rights may be exercised before the agreement terminates or within a reasonable period afterward. Article XI further provides that areas and facilities made available to the United States need not be left in their original condition. The treaty thus regulates the treatment of American military property and improvements, including arrangements relevant to the eventual return of facilities.
Ownership of military property does not establish ownership of the underlying territory. A building, installation, or item of equipment may belong to the United States while the land remains under Danish sovereignty. The treaty's distinction between property rights and territorial authority is particularly relevant where American forces construct permanent facilities or undertake substantial improvements within an agreed defense area.
American operations are also subject to obligations concerning relations with Danish authorities and Greenland's local population. Article VI requires the United States to cooperate to the fullest degree with Denmark and its authorities in carrying out operations under the agreement. It further requires both the U.S. government and American nationals in Greenland to give due respect to the laws, regulations, and customs concerning the local population and Greenland's internal administration (United States and Denmark, 1951, Article VI).
The original Article VI contained an additional restriction concerning contact between American personnel and the local population when Danish authorities considered such contact undesirable for defense operations. That restriction was revoked in 1986. Article 3(1)(a) of the Igaliku Agreement expressly confirms that the final clause of Article VI's second sentence is no longer effective (United States and Denmark, 2004, Article 3(1)(a)).
The revocation was limited to that particular restriction. It did not eliminate Article VI's remaining obligations concerning cooperation with Danish authorities and respect for Greenland's laws, regulations, customs, and internal administration. The applicable legal position consequently requires the original treaty to be read alongside its subsequent amendments, preserving the distinction between American military authority, Denmark's continuing sovereignty, and the obligations governing relations with Greenland's inhabitants.
5. The 2004 Igaliku Agreement and Greenlandic Participation
The Igaliku Agreement, signed on August 6, 2004, amended and supplemented the 1951 Defense of Greenland Agreement and relevant subsequent arrangements. Its adoption followed substantial changes in the American military presence, including a reduction in the number of defense areas. Greenland's constitutional position had also evolved since the original treaty was concluded. The amendment addressed these developments while retaining the bilateral defense relationship between the United States and Denmark (United States and Denmark, 2004, Preamble).
Greenland had ceased to be a Danish colony under the constitutional changes of 1953 and acquired Home Rule in 1979. The 2004 agreement acknowledged this development and Denmark's practice of consulting Greenland's Home Rule Government on affairs of state of particular importance to the territory. It was signed by representatives of the United States and the Kingdom of Denmark, including a representative of Greenland's Home Rule Government. Greenland's participation was expressly recognized within the bilateral agreement; it did not make Greenland an independent contracting state.
The constitutional arrangements changed again when the Act on Greenland Self-Government entered into force on June 21, 2009, replacing the Home Rule system. The Act expanded Greenlandic self-government while leaving foreign, defense, and security policy among the responsibilities that cannot be transferred to Greenlandic authorities under the existing constitutional arrangement. The reference to the Home Rule Government in the Igaliku Agreement reflects the institution that participated in 2004; the subsequent legislation did not itself amend the defense treaty (Denmark, 2009).
The Igaliku Agreement made specific changes to the treatment of defense areas and the legal status of American personnel. It also established consultation arrangements concerning significant changes to military operations and facilities. Separate declarations adopted at Igaliku addressed economic and technical cooperation and environmental protection. These instruments formed part of the wider diplomatic arrangements but must be distinguished from the provisions that directly amended the 1951 treaty.
5.1 Thule Air Base and the Designation of Defense Areas
Article 1 of the Igaliku Agreement identified Thule Air Base as Greenland's only defense area. The provision reflected the reduction of the larger network of military areas associated with the original defense arrangements. It did not extinguish the possibility of establishing additional areas: the amendment expressly retained the application of Article II of the 1951 agreement to their designation (United States and Denmark, 2004, Article 1(1)).
The amended arrangements also provided for the flags of Denmark, Greenland, and the United States to fly over Thule Air Base. Danish and Greenlandic authorities were to assist American authorities with the base's protection and internal security when requested and appropriate, consistently with existing agreements and arrangements. These provisions recognized Greenlandic participation in local cooperation without transferring operational command or changing the requirement for agreement on additional defense areas (United States and Denmark, 2004, Article 1(2)).
On April 6, 2023, Thule Air Base was renamed Pituffik Space Base. The name uses the traditional Greenlandic designation of the region and reflects the installation's role in the U.S. Space Force. The renaming concerned the installation's identity and military organization; it did not itself amend the defense treaty or grant additional rights to establish military facilities elsewhere in Greenland (United States Space Force, 2023).
5.2 Greenlandic Consultation and Local Cooperation
Article 3 of the Igaliku Agreement provides for consultation and notification before significant changes to American military operations or facilities in Greenland. The United States undertakes to consult with and inform the government of the Kingdom of Denmark, including Greenland's Home Rule Government, before implementing such changes. The provision operates consistently with the amended defense treaty and the memorandum of understanding of March 13, 1991, without prejudice to other relevant agreements and arrangements (United States and Denmark, 2004, Article 3(1)(c)).
The amendment separately addresses exceptional planned landings by military aircraft outside airports. In these circumstances, the United States consults with and informs the Danish government, including the Greenlandic authorities, to ensure appropriate protection of the environment and hunting areas. This requirement concerns a particular use of military access rights that may affect activities and locations beyond established installations (United States and Denmark, 2004, Article 3(1)(b)).
Greenland's Home Rule Government was also given the possibility of appointing a representative whom the American commanding officer at Thule would consult on local affairs affecting that government. Article 3(2)(a) expressly preserves the position of the Danish liaison officer. The arrangement establishes an additional channel for Greenlandic concerns without altering the military command relationships provided for elsewhere in the defense agreements.
Questions concerning the American military presence may be raised through a broader consultation procedure. Article 3(2)(b) calls for consultation without undue delay on matters covered by the 1951 agreement and the Igaliku amendment. Where a question cannot be resolved locally, consultation may proceed through the Permanent Committee or diplomatic channels. The provision supplies a means of addressing unresolved issues without establishing a separate court or transferring military command to the consultative bodies.
These arrangements do not confer a general Greenlandic veto over American operations. Consultation and notification are distinct from the mutual agreement required under Article II of the 1951 treaty for the establishment of additional defense areas. Greenlandic authorities participate through the arrangements specified in the amendment and the Kingdom's constitutional structure; their consultative role is not equivalent to independent treaty-making authority over defense policy.
The accompanying Joint Declaration on Economic and Technical Cooperation envisaged cooperation between the United States and Greenland in fields including research, energy, education, tourism, and trade. It also provided for a Joint Committee to coordinate activities and consider projects, with financial contributions subject to funding approval and applicable national procedures. These arrangements concerned cooperation beyond military operations and did not amend the treaty's rules on defense-area designation (Joint Declaration on Economic and Technical Cooperation, 2004, paragraphs 1–3).
A separate Joint Declaration on Cooperation on the Environment in Greenland addressed pollution prevention, protection of wildlife and habitats, environmental information, and access to the defense area for environmental purposes. It envisaged an Environmental Subcommittee and recognized that access by Danish and Greenlandic representatives would remain subject to military, security, and safety considerations. The declaration contains cooperation undertakings and statements of intended action expressed in its own terms. Its provisions should not be treated as additional military-access rights or assumed to have the same legal effect as the treaty amendment (Joint Declaration on Cooperation on the Environment in Greenland, 2004, paragraphs 1–5).
6. Jurisdiction and the Status of U.S. Personnel
Responsibility for operating a military installation does not determine, on its own, which state may prosecute an offense committed there. The 1951 Defense of Greenland Agreement originally addressed jurisdiction over American personnel and other persons within U.S.-operated defense areas. It also established arrangements concerning the entry and departure of personnel and the treatment of supplies and property.
A different jurisdictional regime became applicable through the NATO Status of Forces Agreement (NATO SOFA), signed on June 19, 1951. That agreement regulates the status of forces serving in the territory of another NATO member. The Igaliku Agreement confirms that NATO SOFA has applied in Greenland since 1955 and specifies how its provisions interact with those of the original Greenland treaty (United States and Denmark, 2004, Article 2(1)).
The applicable jurisdictional rules depend on the person's legal status, the conduct involved, and the respective powers of the sending and receiving states. American operational responsibility for a defense area must be distinguished from the allocation of criminal jurisdiction under the agreements governing military personnel and qualifying civilians.
6.1 Jurisdiction Under the Original Treaty
Article VIII of the 1951 agreement originally granted the United States the right to exercise exclusive jurisdiction over defense areas for which it was responsible under Article II(3). It also extended American jurisdiction to offenses committed in Greenland by the military and civilian personnel described in Article VII and by members of their families. Other persons within American-operated defense areas were covered, with an express exception for Danish nationals (United States and Denmark, 1951, Article VIII).
The original provision thus combined jurisdiction connected to American personnel with jurisdiction arising from a person's presence within a defense area. Its reach extended beyond military disciplinary proceedings. At the same time, the express exception for Danish nationals limited the jurisdiction granted over other persons present in those areas.
Article VIII permitted the United States to turn over to Danish authorities in Greenland, for trial, a person who had committed an offense within an American-operated defense area. This possibility qualified the exercise of the jurisdiction granted by the original treaty. It did not establish the detailed rules for concurrent jurisdiction and priority subsequently applicable under NATO SOFA.
Article X of the 1951 agreement anticipated that a NATO agreement concerning the subjects addressed by Articles VII–IX might supersede incompatible provisions. The Igaliku Agreement later confirmed the supersession of Article VIII. Its original wording remains relevant to the history of American military rights in Greenland but no longer provides the governing jurisdictional rule (United States and Denmark, 1951, Articles VIII and X; United States and Denmark, 2004, Article 2(3)).
6.2 The NATO Status of Forces Agreement
Article 2 of the Igaliku Agreement expressly establishes the relationship between NATO SOFA and the remaining personnel provisions of the Greenland defense treaty. Article VIII is superseded by the corresponding provisions of NATO SOFA, while Articles VII and IX continue to apply as supplementary arrangements between the parties. The amendment also deletes the first sentence of Article X and identifies NATO SOFA as the agreement referred to in its remaining sentence (United States and Denmark, 2004, Article 2(2)–(5)).
NATO SOFA defines the categories of persons to which its provisions apply. A member of a force belongs to the armed services of a contracting state and is present in another contracting state's territory in connection with official duties, subject to the agreement's qualifications. A civilian component consists of qualifying civilian personnel accompanying a force who are employed by an armed service of the sending state and meet specified nationality and residence conditions. A dependent is a qualifying spouse or child of a member of a force or civilian component (NATO Status of Forces Agreement, 1951, Article I).
These definitions do not automatically include every civilian working at an American installation. An independent contractor does not become a member of a civilian component merely by performing work at the base, and the agreement does not treat every relative of military personnel as a dependent. The applicable status must be established under the relevant definition and any other applicable arrangement. This distinction is especially important because Article VII of the Greenland defense treaty extends certain customs and tax provisions to civilians employed by or under contract with the U.S. government. Those supplementary benefits do not, by themselves, bring every contractor within NATO SOFA's criminal-jurisdiction regime (United States and Denmark, 1951, Article VII; NATO Status of Forces Agreement, 1951, Article I).
Article VII of NATO SOFA distinguishes exclusive from concurrent jurisdiction. The sending state's military authorities have exclusive jurisdiction over persons subject to its military law for offenses punishable under the sending state's law but not under the receiving state's law. Conversely, the receiving state has exclusive jurisdiction over covered personnel and dependents for offenses punishable under its law but not under the sending state's law. The sending state's jurisdiction remains dependent on the powers conferred by its own military law (NATO Status of Forces Agreement, 1951, Article VII(1)–(2)).
Where both states have jurisdiction, Article VII(3) determines which has the primary right to exercise it. The sending state's military authorities have priority over specified offenses committed by members of its force or civilian component, including offenses solely against the sending state's property or security, certain offenses solely against the person or property of another member or dependent, and offenses arising from acts or omissions performed in the course of official duty. The receiving state has priority in other cases of concurrent jurisdiction.
Priority does not eliminate the other state's jurisdiction. A state that decides not to exercise its primary right must notify the other state as soon as practicable. The agreement also requires sympathetic consideration of a request to waive priority where the requesting state considers the waiver particularly important. Article VII contains further provisions concerning arrest, custody, investigations, evidence, and notification of the disposition of cases (NATO Status of Forces Agreement, 1951, Article VII(3), (5)–(6)).
The jurisdictional provisions do not confer a general sending-state power over nationals or ordinary residents of the receiving state. Article VII(4) expressly limits such authority, subject to its exception for members of the sending state's force. The person's status and the connection between the alleged offense and official duties must be examined before the relevant jurisdictional rule can be identified.
The supplementary provisions of the Greenland defense treaty remain significant outside the allocation of criminal jurisdiction. Article VII addresses the importation and exportation of supplies, customs treatment, and taxation connected with defense operations. Article IX concerns the admission and departure of personnel and family members whose presence is required for operations under the agreement. Their continued application must be read alongside NATO SOFA without restoring the superseded jurisdictional provisions of Article VIII (United States and Denmark, 1951, Articles VII and IX; United States and Denmark, 2004, Article 2).
7. NATO, Treaty Amendment, and Duration
The 1951 Defense of Greenland Agreement was concluded within the defense arrangements established by the North Atlantic Treaty. Its preamble records NATO's request that Denmark and the United States negotiate arrangements for the use of facilities in Greenland by forces of member states. Article I connects their individual and joint responsibilities in Greenland to NATO plans for collective defense (United States and Denmark, 1951, Preamble and Article I).
The North Atlantic Treaty establishes collective-defense obligations but does not itself designate American military bases in Greenland or define the operational powers exercisable there. Those questions are addressed by the bilateral defense agreement. Article II requires the two governments to agree on defense areas and determine responsibility for their operation. The existence of NATO defense responsibilities does not dispense with those requirements.
Article IV provides for the wider allied use of Greenland's defense areas. In connection with the defense of Greenland and the North Atlantic Treaty area, facilities are to be made available, so far as practicable, to vessels, aircraft, and armed forces of other NATO members. This arrangement facilitates collective defense without making NATO itself a contracting party to the Greenland agreement or assigning it sovereignty over the territory (United States and Denmark, 1951, Article IV).
The treaty also establishes procedures for addressing questions about its interpretation and operation. Article XIII(1) preserves existing command relationships. Under Article XIII(2), questions of interpretation arising in the agreement's application are submitted to Denmark's minister for foreign affairs and the United States ambassador to Denmark. This is a diplomatic procedure rather than a separate judicial mechanism.
Article XIII(3) permits either government, after the agreement has operated for a reasonable period, to propose a review in light of experience or amended NATO plans. Both governments undertake to give such proposals sympathetic consideration, but modifications require mutual consent. Changes in military requirements may provide grounds for review without automatically changing the rights and obligations established by the treaty (United States and Denmark, 1951, Article XIII).
The need for formal amendment depends on the nature of the proposed change. Activities already authorized within an agreed defense area may be undertaken under existing treaty powers, subject to applicable conditions and consultation requirements. The designation of an additional defense area, by contrast, remains governed by Article II. The Igaliku Agreement preserved that distinction while introducing consultation arrangements concerning significant changes to military operations and facilities.
Article XIV(2) provides that the 1951 agreement, as an instrument implementing the North Atlantic Treaty, remains in effect for the duration of that treaty. Article 4 of the Igaliku Agreement establishes a corresponding rule for the amendment, which entered into force upon signature on August 6, 2004. It also permits the amendment to be changed by mutual agreement (United States and Denmark, 1951, Article XIV(2); United States and Denmark, 2004, Article 4).
These duration provisions establish the periods contemplated by the parties. They do not prevent the parties from agreeing to subsequent modifications or resolve every question that might arise under applicable treaty law. The legal operation of the Greenland defense arrangements depends on the original instrument and the provisions that have remained applicable following subsequent amendments, supersession, and revocation.
Also read
Conclusion
The 1951 Greenland Defense Agreement grants the United States extensive rights to maintain military facilities and conduct defense activities in Greenland. Those rights arise from an agreement with Denmark, which retains sovereignty over the territory. The treaty distinguishes the designation of defense areas, the exercise of operational powers within them, and access to other parts of Greenland.
The 2004 Igaliku Agreement modified important aspects of that arrangement. It identified Thule Air Base as Greenland's sole defense area at the time, retained the procedure for establishing additional areas, and introduced express consultation arrangements involving Greenlandic authorities. It also confirmed the application of NATO SOFA and the supersession of the original treaty's jurisdictional provisions.
The scope of American military authority is consequently determined by the rights granted under the defense agreement and the provisions that continue to apply alongside its amendments and NATO SOFA. Greenlandic consultation forms part of those arrangements, but it is distinct from the agreement required between the contracting governments to designate new defense areas. Military access, operational responsibility, criminal jurisdiction, and territorial sovereignty remain separate legal questions governed by their respective provisions.
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