Examining Extremism: Kurdistan Workers' Party (PKK)

The Kurdistan Workers’ Party (Partiya Karkerên Kurdistanê or PKK) emerged in the late 1970s as a Marxist-Leninist insurgency with aspirations of Kurdish independence from Turkey. Almost 40 years after beginning its insurgency, the PKK is now embedded in a regional constellation of groups that seek international legitimacy and Kurdish autonomy. The PKK continues to pose a threat to Turkish security forces and civilians, but its main impact beyond the region in recent years has been to complicate the Turkey-U.S. relationship. Ankara sees the group as a major security threat, but the United States works with its Syrian offshoot—now embedded in a Kurdish-led coalition called the Syrian Democratic Forces (SDF)—despite having designated the PKK as a foreign terrorist organization. This entry in Examining Extremism provides an overview of the PKK, its recent activities, and the problems it creates for the relationship between two NATO allies.



The PKK’s history can be divided into four distinct phases. From 1984 through 1999, the PKK waged a rural insurgency in Turkey. From 1999 to 2013, the PKK and Turkish security agencies engaged in secret talks while fighting continued. From 2013 to 2015, Turkey and the PKK engaged in a formal peace process. Since 2015, the conflict has grown increasingly regionalized, with Turkey pursuing the PKK and its affiliates into Iraq and Syria. During the last 40 years, the conflict has been frequently interrupted by ceasefires, many of which were declared unilaterally by the PKK.

First insurgency (1984–1999): The PKK was founded in the late 1970s by a group of Kurdish leftists in Turkey and officially began its violent campaign against the Turkish government in 1984. The rise of the PKK was fueled by Ankara’s suppression of Kurdish culture and human rights abuses committed against Turkey’s Kurdish population. For the first 15 years of the group’s struggle against the Turkish government, PKK leader and cofounder Abdullah Öcalan lived in exile in Syria, where the group received support from the government of Hafez al-Assad. The PKK’s insurgency in southern Turkey continued—interrupted by occasional ceasefires—until 1998, when Öcalan was expelled from Syria, arrested in Nairobi, and found guilty of secessionist and terrorist activities in Turkey. A Turkish court sentenced Öcalan to death, although his sentence was commuted to life imprisonment.

Secret talks (1999–2013): Öcalan’s arrest marked the beginning of a nearly 15-year effort to negotiate an end to the conflict. The PKK announced a five-year unilateral ceasefire in 1999, and during the next five years, Öcalan and Turkish military officials conducted secret face-to-face talks aimed at exploring the possibility of peace negotiations. The ceasefire broke down in 2004, but the talks continued, transforming into a public peace process in 2013.

Peace process (2013–2015): The Turkish government and PKK sought a negotiated resolution to the conflict in a formal peace process, but domestic Turkish politics and the emergence of a PKK offshoot called the Democratic Union Party (PYD) as a major player in the Syrian civil war eventually doomed the talks. Ankara terminated the negotiations in 2015 amid tensions related to Turkey’s bombing of Kurdish military positions in northern Syria and large protests aimed at changing Turkish policy toward the PYD. Fighting quickly resumed and reached new heights in 2015 and 2016, with the number of PKK attacks in Turkey reaching levels unseen since Öcalan’s arrest.

Regional conflict (2015–present): Since the collapse of the peace process, the violence associated with the Turkey-PKK conflict has spread beyond the PKK’s traditional operating areas in southern Turkey. The 2015–2016 escalation saw significant violence in Turkey’s cities for the first time, and a Turkish counterinsurgency campaign in northern Iraq has accounted for an increasing proportion of violence associated with the Turkey-PKK conflict since 2018. Turkey has also conducted several large-scale military interventions into northern Syria in order to push the PYD away from its border. The PKK and Turkish security forces have killed at least 6,000 people since 2015, including 600 civilians, 1,300 members of state security forces, and 4,000 members of the PKK or Kurdistan Freedom Hawks (TAK), an more extreme offshoot with a murky relationship to the PKK.

U.S. military support to the PYD has further complicated the conflict over the past ten years. What began as a campaign of airstrikes and airdrops in support of PYD forces fighting the Islamic State in Iraq and Syria (ISIS) in 2014 grew into an established counterterrorism partnership in the following years, with the United States providing arms, training, and combat support to PYD forces in Syria over Turkish objections. The relationship with the United States has not delivered the PYD complete freedom from Turkish attacks, however. For example, President Donald Trump endorsed a Turkish military operation that pushed SDF forces back from the border with Turkey in 2019.


The PKK is primarily a Kurdish nationalist organization, and Öcalan remains the group’s ideological leader. Originally a Marxist-Leninist group seeking the formation of an independent Kurdish state, the PKK’s official ideology is now a novel political philosophy called “democratic confederalism” that advocates for a decentralized system of local self-governance. Such a form of government remains mostly theoretical, and the practical impact of Öcalan’s changing philosophy has been a shift in the PKK’s stated goal from formal independence to Kurdish self-governance within the borders of existing states. Repeated ceasefires and accompanying statements by the PKK suggest that the group desires a negotiated solution to the conflict.

The Turkish government disputes the veracity of the PKK’s transformation. Turkey continues to describe the ideology of the PKK as “revolutionary Marxism-Leninism and separatist ethno-nationalism,” unchanged since the group’s formation. Under this account, the PKK still maintains its secessionist aspirations, couching them in new language in a bid for international legitimacy.

Evidence regarding the implementation of democratic confederalism in PKK-controlled areas fails to resolve the contradiction between the Turkish account and that of the PKK itself. Analysis of the PKK’s control of Sinjar, Iraq, from 2014 through 2017 indicates that implementation of Öcalan’s democratic confederalism was partial at best. Interviews revealed that community-level mechanisms for service provision and discussion coexisted with a PKK-dominated political structure with little room for dissent, hardly the ideal of local self-governance described in Öcalan’s writings.

Organizational Structure

The PKK is a hierarchical organization with developed institutions, albeit one that maintains something of a cult of personality around Öcalan's leadership. Öcalan remains the formal head of the PKK and continues to exercise his authority by publishing from prison and communicating with other leadership bodies within or affiliated with the PKK. The group’s structure is formally divided between a political arm consisting of various governing committees and its military forces, the main body of which is the People’s Defense Force (HPG). Both are subdivided along regional lines, with geographically defined subgroups exercising authority over their respective areas of operation. There is limited evidence of significant intra-PKK tensions or infighting, and the group appears to maintain a unified command structure despite the difficulties associated with Öcalan’s imprisonment.

The PKK’s international linkages are complicated. The PKK is inseparable from the Kurdistan Communities Union (KCK), an umbrella organization formed in 2005. Öcalan is the official leader of the KCK, and the organization’s founding document states that the KCK is based on PKK ideology. The KCK is governed by a supranational People’s Assembly and Executive Council, with authority devolved according to a federalist structure with levels going down to that of the village or neighborhood. The KCK incorporates PKK-affiliated Kurdish groups including the PYD in Syria, the Kurdistan Free Life Party (PJAK) in Iran, and the Kurdistan Democratic Solution Party (PÇDK) in Iraq.

The relationship between the PKK, PYD, People’s Defense Units (YPG), Women’s Protection Units (YPJ), and the SDF are vital to the group’s influence on international politics. The YPG and YPJ are the armed wings of the PYD, and the SDF is an umbrella group incorporating the YPG, YPJ, and several non-Kurdish groups that serves as the main U.S. counterterrorism partner in Syria. The Inspector General for Operation Inherent Resolve revealed that the U.S. spent at least $32.3 million PYD-affiliated groups between April 2022 and March 2023 and the 2024 Department of Defense (DOD) budget request specified that the U.S. had allocated $155 million in 2022 and $160 million in 2023 to the the Counter-ISIS Train and Equip Fund (CETF) for use in Syria, where PYD-affiliated groups are almost certainly the main recipients of support. More significant are the training and combat support that the United States provides to the SDF. Many non-state groups can raise comparable amounts of money—the Islamic State at its peak made well over $1 billion per year—but very few benefit from such a close relationship with one of the world’s most advanced militaries.

The links between the PKK, PYD, and SDF are undeniable. PKK members have fought along the YPG in Syria, and the SDF commander in chief is Mazloum Abdi, a former PKK member who knew Öcalan when he was living in Syria. The overlap between the PKK, PYD, and SDF also fits a larger pattern of fluid group affiliation within the KCK. Despite its main campaign being against the Turkish state, the PKK incorporates Kurds from countries with their own KCK branches into its military arm. A Kurdish fighter in Syria interviewed in 2015 also observed that her affiliation did not matter because “it’s all PKK.” The result is that Turkey sees international support to the PYD and SDF as support to the PKK despite PYD denials of ties beyond those of ideology and shared history. The United States attempted to mollify Turkey's concerns by urging the creation of the SDF in 2015, but the tensions remain unresolved.

The impact of PKK internationalization is not limited to the United States. The PKK also maintains an active recruiting and financing infrastructure in Europe despite EU counterterrorism restrictions. For example, a French law enforcement investigation alleged that a local Kurdish organization that came to investigators’ attention in 2022 collects approximately $2.2 million each year in informal taxes from diaspora communities in southeast France. The head of Sweden’s public security agency has also acknowledged that the PKK raises significant funds in Sweden, although she declined to specify how much money the group raises there. The German government has also asserted that more than 300 Germans have traveled to areas controlled by PKK affiliates, observing that some had joined combat units. The German government has also emphasized PKK informational activities in Europe, alleging the existence of PKK-affiliated media organizations based in the Netherlands and Norway. The PYD has also made overt political connections in Europe, opening offices in European capitals including Berlin, Paris, Moscow, and Stockholm.

Tactics and Targets

The PKK employs a mix of guerrilla and terrorist tactics. It uses a variety of typical insurgent weaponry including improvised explosive devices (IEDs), car bombs, grenades, small arms, mortars, rocket-propelled grenades (RPGs) , man-portable air defense systems (MANPADs), and anti-tank weapons. It has also conducted suicide bombings since 1996.

The PKK’s insurgency has largely been focused on southern Turkey and the Kurdistan Region of Iraq (KRI), where the group, including its leadership, has long maintained a significant presence in the Qandil Mountains. The PKK primarily targets Turkish security forces, although it has targeted government officials and civilians it accuses of collaborating with the Turkish government. It has also clashed with KRI security forces as part of a broader conflict with the Kurdistan Regional Government, which is aligned with Turkey. It has also repeatedly attacked oil pipelines in its areas of operation. It mostly conducts small-arms, RPG, and mortar attacks on the positions of security forces; small-arms attacks on civilians; and IED attacks against the full range of targets.

For most of the group’s history, the PKK waged a rural insurgency, but the collapse of the peace process in 2015 led to a two-year spasm of urban violence. In these urban operations, the PKK relied on young local militias such as the Patriotic Revolutionary Youth Movement (YDG-H) to barricade neighborhoods, likely in an attempt to spur a broad uprising against the Turkish government.

The experiment with urban warfare was not a success. High casualties were reported on both sides of the conflict during the PKK’s occupation of urban centers, and 200 civilians were killed and 10,000 displaced during the eight months that urban fighting was at its peak. The Turkish military’s crackdown alienated the country’s Kurds from the Ankara government, but the PKK gained little from the conflict. As a result, the PKK returned its focus to the type of rural insurgency that it had engaged in since 1984.

Threat Assessment

The PKK poses a minimal threat to the Turkish state. Throughout its history, the PKK has rarely established control over territory in Turkey, its control of territory outside of Turkey has been eroding rather than expanding, and it has officially revoked its separatist goals. Despite the limited threat to the Turkish state, the PKK and its associated groups continues to pose a threat to Turkish civilians and security forces, especially in areas near the Turkey-Syria and Turkey-Iraq borders. However, the amount of violence associated with Kurdish groups in Turkey has been declining for several years, suggesting a declining threat within the country. At the same time, PKK-related violence outside of Turkey has increased as the Turkish military has increasingly pursued the group into Iraq and Syria, where Turkish strikes have killed civilians in several prominent incidents.

The PKK poses a minimal threat to American citizens or government personnel. PKK affiliates work closely with U.S. military personnel in Syria, and most accounts suggest that the U.S. military has a good working relationship with its SDF partners in Syria. Öcalan's rhetoric also grew increasingly favorable of the United States after the end of the Cold War, and neither the PKK’s official nor its alleged separatist ideology suggests a major terrorist threat to the United States.

The main threat to U.S. interests derives from its position as a NATO ally of Turkey and a supporter of the PKK-affiliated SDF. The U.S. partnership with the SDF is a major source of friction in the U.S.-Turkey relationship. Other countries’ relationships with the PKK or PYD have also affected the broader NATO alliance, particularly due to Sweden's alleged support of the PKK. Sweden's relatively lax counterterrorism laws, protests by PKK sympathizers, and engagement with the PYD have increased tensions between Turkey and Sweden, as has a spate of Quran burnings unrelated to the PKK. Although Ankara dropped its objections to Sweden’s membership in July 2023, the Turkish veto delayed Sweden’s accession to the alliance when NATO leaders wanted to ensure a smooth path to membership. Continued collaboration between the United States and the SDF will generate friction between Turkey and the United States as long as Ankara sees the PKK as one of its most important security threats.

Alexander Palmer is a research associate in the Transnational Threats Project at the Center for Strategic and International Studies (CSIS) in Washington, D.C. Mackenzie Holtz is a research intern with the Transnational Threats Project at CSIS.

Special thanks to Katherine Stark for editing and publication support.

Alexander Palmer
Associate Fellow, Warfare, Irregular Threats, and Terrorism Program

Mackenzie Holtz

Research Intern, Transnational Threats Project