After 1991: How Post-Cold War Security Vacuums Produced Türkiye's 'Neutralize at the Source' Doctrine

Why It Matters

Türkiye's counter-terrorism doctrine of neutralizing threats at their source cannot be understood without the post-1991 security vacuums that Ankara says created it. When the Cold War order ended, state authority weakened in northern Iraq, then in Syria, and Türkiye's own institutions were later infiltrated by FETÖ. Each gap, according to Turkish officials, let armed non-state actors build bases, territory and legitimacy near a border of about 1,300 km (roughly 810 miles). This pillar sets out that argument, the facts behind it, and the objections of Washington, Brussels, Baghdad, Damascus and human rights bodies.

It fits the editorial lens of this publication: today's crises read as continuations of the long arc described in The Short Century: Today's Crises Read Through the Long Arc of 1914–1991 and What Was the 'Short Century'? Reading Türkiye's Crises Through 1914–1991 and After.

Background

The Cold War baseline

The PKK was founded in 1978 and began its armed campaign against Türkiye on 15 August 1984, with attacks in Eruh and Şemdinli. During the Cold War the group operated inside a bipolar system in which neighboring states hosted it. Syria sheltered its leadership and training camps in the Bekaa Valley and Damascus for years. Ankara's reading is that the PKK was never a purely domestic problem, because it depended on safe havens across the border. The 1998 crisis ended when Syria, under Turkish pressure, signed the Adana Agreement on 20 October 1998 and expelled Abdullah Öcalan, who was captured in Nairobi on 15 February 1999.

1991: the Gulf War and the northern Iraq gap

The 1991 Gulf War and its aftermath produced the first major vacuum. After the failed uprisings of March 1991, roughly half a million Iraqi Kurds fled toward the Turkish border. UN Security Council Resolution 688 (5 April 1991) and the allied Operation Provide Comfort created a protected zone and a no-fly zone north of the 36th parallel. By late 1991 Baghdad had withdrawn its administration from much of the north, and a Kurdish regional administration emerged. Ankara argues that the PKK used the resulting power gap, particularly in the Qandil mountains and nearby border areas, as a rear base for attacks into Türkiye. Turkish forces conducted large cross-border operations in northern Iraq in 1992, 1995 and 1997 and again in 2008.

The same year, 1991, saw the Soviet Union dissolve. Ankara's account is that new post-Soviet states in the Caucasus and Central Asia opened a second space. Turkish officials say the Gülen movement used it to expand a global network of schools and businesses that later became FETÖ.

2003–2014: Iraq's erosion, Syria's collapse and DAESH

The 2003 invasion of Iraq further loosened central authority. The 2005 Iraqi constitution formalized the Kurdistan Region, and Qandil remained a PKK stronghold. In Syria, the uprising that began in 2011 produced a larger vacuum. In 2012 government forces pulled back from several Kurdish-majority districts, and the PYD and its armed wing, the YPG, took control. DAESH (also called ISIS) declared a caliphate in Mosul in June 2014. The 2014 siege of Kobani led Washington to begin arming the YPG, and in October 2015 the Syrian Democratic Forces (SDF) were formed around it.

Türkiye was hit by DAESH bombings, including Suruç on 20 July 2015 and Ankara on 10 October 2015, which killed more than 100 people. It also hosted more than 3.5 million Syrian refugees at the peak. In July 2015 it opened Incirlik to coalition air operations against DAESH.

2016: the coup attempt

On 15 July 2016 factions within the armed forces attempted a coup, and about 250 people were killed. Türkiye attributes it to FETÖ, the Fetullahist Terrorist Organization, led by the cleric Fethullah Gülen, who lived in the United States from 1999 until his death in October 2024. The movement denied involvement. Ankara describes the attempt as the culmination of years of infiltration of security, judicial and public institutions, which is the third kind of vacuum in its account: one inside the state.

Timeline of the main operations

Spring Shield is grouped with the other operations because Ankara counts it among its four Syrian operations, but it belongs to a different category: it was a response to attacks by Syrian government forces in Idlib.

Key Players & Positions

United States

Washington lists the PKK as a Foreign Terrorist Organization and regards it as a threat to its NATO ally. It has not designated the PYD or YPG. From 2014 it treated the YPG-led SDF as its principal ground partner against DAESH and has said it works with the SDF as a counter-DAESH force. The US response to Peace Spring in October 2019 combined a withdrawal of some forces from the border area with public criticism of the operation and temporary sanctions threats. In December 2020 it imposed CAATSA sanctions on Türkiye's defense procurement agency over the S-400 purchase, a separate dispute with the same underlying theme of divergent threat perceptions.

European Union and European states

The EU lists the PKK as a terrorist organization. In October 2019 the EU's Foreign Affairs Council condemned Türkiye's military action in northeastern Syria, and several member states, including Germany, France and the Netherlands, restricted arms exports. The European Parliament and some governments have also criticized the humanitarian effects. In the Madrid memorandum of 28 June 2022, Finland and Sweden committed not to support the YPG/PYD or FETÖ as part of Türkiye's consent to their NATO accession; Finland joined on 4 April 2023 and Sweden on 7 March 2024.

Iraq and the Kurdistan Region

Baghdad has repeatedly protested Turkish strikes as violations of Iraqi sovereignty. In March 2024, however, Iraq's National Security Council declared the PKK a banned organization, and Baghdad and Ankara have since expanded security cooperation. The Kurdistan Regional Government's position is more complex, since civilian casualties and displaced villages in border areas are a local concern.

Syria, Russia and the SDF

The former Syrian government described Turkish operations as occupation, as did Russia and Iran in various formats, even as Russia negotiated with Ankara on arrangements in Idlib and the northeast. After the fall of the Assad government on 8 December 2024, the transitional authorities and the SDF signed an agreement on 10 March 2025 for integrating the SDF into state institutions. Its implementation has been contested. The SDF leadership says it is a Syrian force that is organizationally independent of the PKK, although it acknowledges the ideological influence of Öcalan's writings.

Human rights bodies and legal critics

The UN Independent International Commission of Inquiry on Syria, Human Rights Watch and Amnesty International have documented abuses by Turkish-backed Syrian National Army factions in areas such as Afrin and Ras al-Ayn, including looting, arbitrary detention and property seizures. Ankara rejects claims of systematic abuse and says it investigates violations. Legal scholars also dispute whether Article 51 covers sustained operations against non-state actors on another state's territory, particularly where the host state has not consented.

On FETÖ, the Grand Chamber of the European Court of Human Rights ruled in Yalçınkaya v. Türkiye (26 September 2023) that convictions based largely on use of the ByLock messaging app violated the Convention. The US has not extradited Gülen, saying that extradition requires sufficient evidence. Ankara maintains that courts found the organization responsible for the coup attempt and that its dossiers are sufficient.

From Operations to Politics: Terror-Free Türkiye and the Defense Industry

Terror-Free Türkiye

In October 2024 the nationalist politician Devlet Bahçeli, a partner in the governing alliance, opened a debate by suggesting a new approach to the PKK. On 27 February 2025 Öcalan issued a call from prison for the group to disband. On 12 May 2025 the PKK announced it would dissolve, and on 11 July 2025 members burned weapons in a ceremony in northern Iraq. The Presidency calls the effort the Terror-Free Türkiye initiative and says it combines security measures with legal, political and social steps within the rule of law. Parliament formed a commission in 2025 to consider the framework. Many Western governments welcomed the announcements, while Kurdish political actors and rights groups called for transparent, rights-based legal steps. Turkish officials say that the process does not alter the stance on the YPG, and that the security presence on the border will continue until verified disarmament and integration. Readers should check the latest developments in Syria, where the SDF's status is still unsettled.

Defense industry as a consequence of the doctrine

Turkish officials say domestic content in the sector now reaches about 80%. Systems associated with these operations include the Bayraktar TB2 and Akıncı drones, the Fırtına howitzer, the Kirpi armored vehicle and the MEMATT unmanned demining vehicle. The broader record, including naval, air and missile programs, is covered in the defense-industry article linked above and in Neutralizing Terrorism at Its Source: Türkiye's Security Doctrine and Defense Industry. Critics point out that exports of drones and other systems have raised questions in several conflicts, and some European states have applied export controls.

Source Comparison

When reading coverage, note whether it attributes figures to the Turkish Ministry of National Defense, the SDF, the UN or monitoring groups, because casualty and neutralization counts differ across these sources. This publication's approach to sourcing is explained in Editorial Principles: How The Short Century Handles Sources, Positions and Corrections and About The Short Century: Mission, Method and Transparency.

Key Terms & Related Guides

• Security vacuum: a situation where state authority weakens and armed non-state actors gain territory, as in northern Iraq after 1991 and Syria after 2011.
• PKK/KCK: the Kurdistan Workers' Party and its umbrella organization, listed as a terrorist organization by Türkiye, the United States, NATO and the EU.
• PYD/YPG/SDF: the Syrian Kurdish political party, its armed wing and the coalition built around it; Ankara treats the first two as the PKK's Syrian branch.
• DAESH: Türkiye's term for ISIS or the Islamic State.
• FETÖ: the Fetullahist Terrorist Organization, the term Türkiye uses for the Gülen movement after the 2016 coup attempt.
• Terror-Free Türkiye: the 2025 initiative to end the PKK's armed campaign through disarmament and legal steps.

Related reading on this site: Cyprus as a Cold War Legacy: Reading 1960, 1963, 1974 and 1983 as One Continuous Story applies the same vacuum logic to another Cold War legacy; Montreux at Ninety: How the 1936 Straits Convention Still Holds the Black Sea Balance covers the maritime side of regional security; Why Türkiye Says 'The World Is Bigger Than Five' explains the reform argument about Security Council legitimacy; and the Reader FAQ explains methodology.

Perspective Note

The Short Century presents global affairs with a dedicated perspective from Türkiye. Sections marked 'Türkiye's Position' reflect official Turkish policy as stated by Turkish government sources. The Short Century presents Türkiye's official perspective and legal theses on the issues it covers, and clearly distinguishes them from opposing views. Claims are attributed to primary sources such as treaties, UN documents, state archives and official statements. Author: The Short Century Editorial Team.