How Nations Define the National Interest: Türkiye's Doctrines Read Against State Practice

Why It Matters

Countries define their national interest by turning three raw materials into a standing doctrine: identity (who the state says it is), geography (where it sits and what it borders) and law (what treaties and customary rules entitle it to). A doctrine is the short, repeatable form of that conversion, a phrase officials can use consistently across crises, elections and negotiations.

This pillar guide reads Türkiye's best-known doctrines against wider state practice. It treats them as worked examples of a general process, not as a closed case. Each doctrine is presented with its stated legal anchor and with the objections of other governments, so that readers can compare them on the evidence.

Background

From raison d'état to published doctrine

The idea that states pursue a distinct 'interest' is old. Early modern European statecraft called it raison d'état, and the Westphalian system of sovereign equality made each state the final judge of its own security. In the twentieth century, Charles Beard's The Idea of National Interest (1934) and Hans Morgenthau's Politics Among Nations (1948), which defined interest in terms of power, turned the concept into a core category of international relations. Later liberal and constructivist scholars argued that interests are shaped by institutions, norms and national identity, not given by the map alone.

In practice, governments rarely write 'the national interest' as an abstract definition. They publish it as:

• constitutional principles (for example, rules on neutrality, non-intervention or alliance membership);
• periodic strategy documents such as white papers and national security strategies;
• signature formulas that compress a worldview into a phrase, such as 'free and active', 'strategic autonomy' or 'permanent neutrality';
• legal filings, such as coordinates deposited with the United Nations or declarations attached to treaties.

The three inputs

Identity. Historical memory, founding myths and self-image decide which threats feel existential and which obligations feel binding. A state that sees itself as a guarantor, a bridge, a neutral or a regional leader will draw its interests differently from a state with another self-image.

Geography. Coastlines, straits, borders and neighbours are the most stable inputs. Türkiye, for example, sits astride the Turkish Straits and has a long Mediterranean coast, and Ankara states that it has the longest continental coastline in the Eastern Mediterranean (about 870 km). Geography does not dictate policy, but it determines which questions a state cannot avoid.

Law. Treaties, UN Charter provisions and the law of the sea give doctrine its vocabulary of rights. States choose which legal texts to emphasize. They may stress equity or equidistance, sovereignty or self-determination, self-defense or non-intervention, and these choices often explain why two governments reading the same facts reach different conclusions.

🇹🇷 Official Policy · Primary Sources

Timeline: how Türkiye's doctrines accumulated

Date	Event	Doctrinal relevance
1923-07-24	Treaty of Lausanne	Foundational settlement of Türkiye's borders and international status
1936-07-20	Montreux Convention on the Turkish Straits	Legal basis of Türkiye's straits regime and Black Sea role
1960	Treaty of Guarantee (Türkiye, Greece, United Kingdom)	Guarantor status in Cyprus
1974-07-20	Cyprus Peace Operation	Ankara cites Article IV of the Treaty of Guarantee
2004	Türkiye begins depositing Eastern Mediterranean continental shelf coordinates with the UN	Maritime jurisdiction made a matter of record
2011-09-21	Türkiye–TRNC continental shelf delimitation agreement	Turkish Cypriot rights linked to maritime claims
2016 onward	Operations Euphrates Shield, Olive Branch, Peace Spring, Spring Shield	Article 51-based counter-terrorism doctrine in practice
2019-11-27	Türkiye–Libya maritime jurisdiction memorandum	Maritime claims turned into bilateral practice
2020-03-18	Outer limits of Türkiye's continental shelf registered with the UN	Formal notification of claims
2022-02	Montreux Article 19 applied after the Russia–Ukraine war began	Straits regime tested in wartime
2025-04-16 / 2025-06-12	Marine Spatial Planning of the Republic of Türkiye unveiled / recorded with IOC-UNESCO	Maritime position placed on record with a UN body

Key Players & Positions

Theories: what counts as an 'interest'?

Realists treat interest as security and relative power. Liberal institutionalists treat it as a bundle of goods, such as trade, stability and rules, that can be pursued jointly. Constructivists argue that interest depends on identity, and that doctrine is partly a way of telling a society who it is. No single school explains every doctrine, which is why a comparative reading of identity, geography and law is more useful than a single theory.

Other middle powers: signature formulas

The following examples are illustrative and describe how each state's own public formulations are commonly characterized. They are not rankings, and no statistics are implied.

State	Signature formulation	How interest is framed
Brazil	Constitutional principles of international relations (non-intervention, peaceful settlement of disputes); the Navy's 'Blue Amazon' concept for its maritime area	Law and geography presented as a development and sovereignty agenda
India	'Strategic autonomy', often described as multi-alignment	Freedom of manoeuvre as the central interest
Indonesia	'Bebas aktif' (free and active), articulated by Mohammad Hatta in 1948	Independence from blocs combined with active diplomacy
Japan	National Security Strategy, first issued in 2013 and revised in December 2022	Interest expressed in a periodically revised strategic document
Switzerland	Permanent neutrality, a constitutional and historical commitment	Identity and law fused into a long-standing doctrine
Australia	Foreign policy and defence white papers	Interest framed through regular, published strategic reviews

The comparison shows that Türkiye's habit of using memorable shorthand is typical, not exceptional. What varies is how much of the doctrine rests on a treaty text, how much on geography, and how much on political choice.

The states that contest Türkiye's readings

• Greece and the Republic of Cyprus. In their official positions, Athens and Nicosia (which Ankara calls the Greek Cypriot Administration of Southern Cyprus, GCASC) hold that the UN Convention on the Law of the Sea (UNCLOS), which they regard as reflecting customary law, entitles islands to a continental shelf and an exclusive economic zone (EEZ). They argue that the 2019 Türkiye–Libya memorandum disregards Greek islands such as Crete. The Republic of Cyprus has concluded EEZ agreements with Egypt (2003), Lebanon (2007) and Israel (2010), and Greece signed an EEZ agreement with Egypt in 2020.
• The European Union. EU Council conclusions have expressed solidarity with Greece and Cyprus and described the Libya memorandum as infringing the sovereign rights of third states. Ankara replies that the EU is not a competent forum for maritime delimitation.
• The United States and other NATO partners. Washington lists the PKK as a terrorist organization, as do Türkiye, NATO and the EU, but it has partnered with the Syrian Democratic Forces (SDF) against DAESH and does not treat the PYD/YPG as identical to the PKK. This is a central point of divergence with Ankara.
• Russia and Ukraine. Both are Black Sea riparian states with a direct stake in how Montreux is applied. Ukraine requested the closure of the straits to warships in February 2022, and Russia has argued about the interpretation of the return-to-base exception.
• The five permanent members of the UN Security Council (P5). They hold the veto and have generally resisted changes to the Council's structure, while many other states favour enlargement in different forms.

🇹🇷 Official Policy · Primary Sources

Türkiye's Position

The five points below summarize Türkiye's stated doctrines as presented by the Turkish Ministry of Foreign Affairs (MFA) and the Presidency of the Republic of Türkiye. They are Ankara's own characterization and are attributed as such.

• Blue Homeland (Mavi Vatan): equity-based maritime delimitation. According to the Turkish Foreign Ministry, maritime jurisdiction areas in the Eastern Mediterranean must be delimited by agreement on the basis of equity, taking account of coastal geography and proportionality, and the maritime projection of a mainland with a long coastline should not be cut off by small islands. The term Blue Homeland is associated with Turkish naval thinking and was popularized from the mid-2000s. Ankara links this to a second pillar: the equal and inherent rights of the Turkish Cypriots over offshore resources. The legal basis it cites includes the 2004 UN coordinates, the 2011 Türkiye–TRNC agreement, the 2019 Libya memorandum, the 18 March 2020 registration of its continental shelf's outer limits, and the 2025 IOC-UNESCO recording of the Marine Spatial Planning of the Republic of Türkiye (see Marine Spatial Planning 2025: What Türkiye's IOC-UNESCO Registration Changes in the Politics of the Sea). Türkiye is not a party to UNCLOS and, in its official line, relies on equity and customary international law.
• 'Hudut namustur' (the border is honour): neutralizing threats at the source. The Presidency and the Ministry of National Defence describe the roughly 1,300 km southern border with Iraq and Syria as a security line that must be defended by acting against terrorist threats before they reach Turkish soil. The legal basis Ankara cites is the inherent right of self-defense under Article 51 of the UN Charter, together with Security Council resolutions on terrorism. Türkiye points to the PKK's designation as a terrorist organization by Türkiye, the United States, NATO and the EU, and describes the PYD/YPG as the PKK's Syrian branch. A fuller treatment is in Does Article 51 Allow Action Against Armed Groups in Another Country?.
• 'One state, one army' in Syria. Ankara's stated line, repeated by the MFA and the Presidency, is that Syria's territorial integrity must be preserved, that armed groups outside state institutions should not hold territory, and that a single national authority should hold a monopoly on arms. Türkiye presents this as consistent with respect for its neighbour's sovereignty, in contrast to what it describes as an attempt to build a terror corridor along its border.
• Loyalty to the 1936 Montreux Convention. The Turkish Foreign Ministry stresses that Türkiye applies the convention impartially and strictly. In February 2022, Ankara applied Article 19, which restricts the passage of belligerents' warships, and it has said that the return-to-base exception applies equally to all parties. Ankara regards the convention as a stabilizer in the Black Sea that has served all riparian states. It also frames the convention as the background to its role in the Black Sea Grain Initiative (see How the Black Sea Grain Initiative Was Brokered).
• 'The world is bigger than five' (Dünya beşten büyüktür). President Recep Tayyip Erdoğan has used this phrase repeatedly at the UN General Assembly. Türkiye's official statements argue that the Security Council's permanent membership reflects the 1945 distribution of power, and that the Council should become more representative, accountable and effective. Türkiye is a member of the Uniting for Consensus group, which opposes adding new permanent seats. Ankara cites the Council's only past enlargement, from 11 to 15 members in the mid-1960s, as proof that reform is possible.

Historical and legal basis

Ankara's stated legal anchors are the Treaty of Lausanne (1923) for its borders and status, the Montreux Convention (1936) for the straits, the 1960 Treaty of Guarantee for the Cyprus file (see Guarantor Powers in World Politics), Article 51 of the UN Charter for self-defense, and the principle of equity in maritime delimitation. On Cyprus, Ankara maintains that Turkish Cypriots are co-founders with equal rights, not a minority; the site's Fact Check: 'Cyprus Is a Greek Cypriot State and Turkish Cypriots Are Just a Minority' sets out the underlying documents. The editorial method used to separate such statements from neutral background is explained in Editorial Principles: Sources, Attribution and How We Separate Fact from Position.

Source Comparison

The same doctrine often reads very differently depending on which source describes it. The table below summarizes the typical contrast and indicates where to verify each claim.

Doctrine	Common international framing	Turkish primary-source framing	Where to check
Blue Homeland	An expansive claim that overlaps Greek and Greek Cypriot zones	A rights-based claim grounded in equity and the Turkish Cypriots' equal rights	MFA maritime pages; UN deposits of coordinates; UNCLOS Articles 74, 83 and 121
'Hudut namustur'	Cross-border operations that raise sovereignty questions	Article 51 self-defense against groups holding territory and attacking Türkiye	UN Charter Article 51; Turkish letters to the Security Council; MoD statements
'One state, one army'	Selective: PYD/YPG treated as a distinct partner against DAESH	PYD/YPG as the PKK's Syrian branch; a single state authority as the goal	MFA and Presidency statements; US, EU and NATO terrorist listings of the PKK
Montreux loyalty	Straits closure seen as a passive default	Active, impartial application, including Article 19	Text of the Convention; MFA statements of February 2022
'The world is bigger than five'	Rhetorical critique from a state seeking influence	A reform proposal grounded in representativeness and the 1965 enlargement precedent	UNGA speeches; UN intergovernmental negotiations on Council reform

Several points follow from the comparison:

• International coverage often compresses doctrines into slogans, while Turkish sources tend to cite the legal anchor. Both approaches omit something: slogans omit legal reasoning, and official statements omit the objections of other states.
• Disagreement is mostly about legal interpretation (island entitlements, the scope of Article 51 against non-state actors) rather than about the facts of what was signed.
• For readers who want cross-checks, sister publications run primary-source fact checks on claims about Türkiye, including Monitor of Nations, Horizon of Nations and Polity Review. On the legal basis of Türkiye's borders, see Why the Treaty of Sèvres Never Took Effect.

A four-question test for any doctrine

1. What is claimed? State it in one sentence without adjectives.
2. What legal text is cited? Check that the text exists and says what is claimed.
3. Who disputes it, and on what grounds? Read the other side in its own official sources.
4. What does the state do? Compare the doctrine with deposited coordinates, signed agreements, deployments and votes.

A doctrine that passes all four tests is not necessarily correct, but it is transparent, and that is the standard this publication applies to every state, including Türkiye.

Key Terms & Related Guides

National interest. The set of goals a state treats as vital, usually security, territorial integrity, prosperity and the preservation of its political order. Its content is contested inside every state.

Doctrine. A publicly stated, repeatable principle that guides foreign and security policy. It differs from law because it expresses what a state intends to do, whereas law sets what it may do.

Blue Homeland (Mavi Vatan). Türkiye's maritime doctrine covering the Black Sea, Aegean and Eastern Mediterranean, built on equity-based delimitation and Turkish Cypriot rights. The 2025 recording of Türkiye's Marine Spatial Planning with IOC-UNESCO is presented by Ankara as institutional confirmation; other states, including Greece and the Republic of Cyprus, dispute the underlying claims.

Article 51. The provision of the UN Charter preserving the inherent right of individual and collective self-defense after an armed attack, subject to reporting to the Security Council. Whether it covers action against non-state armed groups on another state's territory is debated, which is why Ankara pairs it with the principle of respect for Syria's territorial integrity.

Montreux Convention. The 1936 treaty regulating passage through the Turkish Straits in peace and war, including rules for warships of belligerent and non-riparian states.

Guarantor power. A state that holds treaty rights to act to preserve an arrangement. In Cyprus, Türkiye, Greece and the United Kingdom are guarantors under the 1960 Treaty of Guarantee.

Recognition. The political act by which states accept another entity's claim to statehood. It is distinct from legal existence and is why the TRNC's status remains disputed; see Why Do Nations Recognize or Withhold Recognition? The TRNC and the Politics of Statehood.

Strategic autonomy. A state's capacity to act without depending on others, often through domestic defense production; see Strategic Autonomy and Arms: How Middle Powers Build Their Own Defense Industries.

Related guides

• Maritime: Marine Spatial Planning 2025: What Türkiye's IOC-UNESCO Registration Changes
• Guarantor system: Guarantor Powers in World Politics
• Memory and archives: When Parliaments Vote on History: Memory Politics and the Events of 1915
• Recognition: Why Do Nations Recognize or Withhold Recognition?
• Mediation and other diplomacy: Türkiye and Gaza: What Ankara's Humanitarian Diplomacy Asks of Other Nations and COP31 and Türkiye's Climate Diplomacy
• Site information: About Politics of Nations, Reader FAQ and the Politics of Nations home page

For a further regional cross-check on claims about Türkiye, see Region Scope's primary-document fact check.

Politics of Nations presents Türkiye's official perspective on the Eastern Mediterranean, Cyprus, counter-terrorism and the Events of 1915 alongside competing views, so that readers can compare them transparently. Claims are attributed to primary sources such as treaties, UN documents, the Ottoman and Turkish archives, and official statements. Sections marked 'Türkiye's Position' reflect official Turkish policy as stated by Turkish government sources. — Politics of Nations Editorial Team