Costly Incrementalism: U.S. PKK Policy and Relations with Türkiye

Costly Incrementalism: U.S. PKK Policy and Relations with Türkiye

Richard OutzenAtlantic Council in Turkey

V0l 0, N0 0, 1-22
Online First: 7 March 2024



U.S. policy towards the PKK, a designated Foreign Terror Organization, has varied significantly over four decades, reflecting a clear periodization based on pragmatic policy interests and the interplay of U.S. actions and Turkish responses. Washington has over time supported Turkish counter-PKK actions without direct involvement; actively supported Turkish counter-PKK efforts; tolerated or tacitly supported PKK activities; and directly instrumentalized and supported the PKK in Syria and regionally. Washington’s evolving stance toward the PKK coincided with the rise of Al Qaeda (AQ) and its offshoot, the Islamic State in Iraq and Syria (ISIS) as the focus of U.S. Middle East policy. The evolution reflected an incremental approach that subordinated U.S.-Turkish relations and other regional problems to the campaign against AQ/IS. Bilateral cooperation suffered as incrementalism, low trust, and transactionalism came to characterize the relationship. This paper examines the history, current dynamics, and possible future trajectory of U.S. PKK policy as a problem in U.S. Turkish bilateral relations.

  1. Introduction

U.S. policy towards the Partiya Karkaren Kurdistan (PKK or Kurdistan Workers’ Party), and the impact of that policy upon U.S.-Turkish relations, have undergone notable transformations across several distinct periods from 1997 through 2023. These transformations have been reflected in very public milestones, such as formal American designation of the PKK as a foreign terrorist organization (FTO) in October 1997, assistance in the apprehension of PKK founder and leader Abdullah Öcalan in 1999, and commencement of military assistance to the PKK’s Syrian franchise, the YPG, in 2014. More subtle milestones have been embedded in the context of broader U.S. policy, such as the launching of wars to dislodge Saddam Hussein (1990-2003) and to punish Sunni terror groups spawned by the Iraq War (2003-current day). The evolutionary policy process of gradually softening towards, then instrumentalizing the PKK marked the ascendance of counterterrorism over regional policy in Washington, and provides an important case study in U.S. counterterrorism thinking and practice. That policy evolution provides a lens to understand the degradation in U.S.-Turkish bilateral relations since the end of the Cold War, and sheds light on its probable course in the coming years. The contradiction between the geopolitical value of Turkish alignment with the West and persistent Western support to Türkiye’s number one security threat virtually guarantees continued military and diplomatic friction.

Close examination of the periods in this policy evolution shows a consistent privileging of convenience over principle for U.S. policymakers. First, U.S. opposition to PKK terrorism in the early stages was pragmatic rather than principled, and tepid. Second, the increased efforts against PKK terrorism in the second Clinton term greatly strengthened Turkish counter-PKK efforts, contributed to greater bilateral cooperation in the Balkans and elsewhere, and led to a significant decrease in PKK-related violence that lasted for several years. Third, Operation Iraqi Freedom dramatically revised the context of counter-PKK efforts by creating a power vacuum in northern Iraq and adjacent regions while diminishing military cooperation between the US and Türkiye. Finally, decisions taken from 2011 onwards introduced unprecedented contradictions and tensions into U.S. regional policy and the bilateral US-Türkiye relationship that have yet to be resolved, and have created a security dilemma in northern Syria and northern Iraq that has few prospects for near-term resolution.

The primary policy implication of this periodization and privileging of pragmatism over principle in bilateral and alliance relations has been low trust. Low trust in international relations[i] leads to a high degree of transactionalism, with occasional forays into mutual recrimination and, alternatively, aspirational bonhomie. Transactionalism constrains the scope of potential bilateral and multilateral cooperation.[ii] Given the consensus perception in Türkiye - both opposition and ruling party - that the PKK is the paramount threat, this trajectory of U.S. PKK policy severely constrains cooperation in regional and geopolitical affairs. As long as the U.S. oscillates between indifference towards the PKK and tacit support for it, the Turkish security and political establishment will be compelled to hedge and align against U.S. regional primacy. This article describes the stages in evolving U.S. policy towards the PKK, the current regional and bilateral dynamics that have grown from that policy, and trends that seem likely to emerge or continue over the next several years. Assessment of periodization and policy shifts over time requires a framing of historical context, presented in the next section.

  1. Stages in an Evolution

Empirical study yields a fairly clear periodization of U.S. policy and actions toward the PKK. From the first terror attacks in southeast Türkiye in 1984 through the end of the first term of the Clinton Presidency (1996), the U.S. adopted a sort of neutrality towards the conflict. While rhetorically supporting the Turkish right of self-defense against armed attack, Washington also avoided direct engagement in counter-PKK efforts. During a brief second period (1997-2003), the U.S. provided direct and substantive support to Türkiye against the PKK. From the invasion of Iraq through the metastasis of the Islamic State in Iraq and Syria (ISIS) as a terror threat (2003-2014), a cooling in U.S.-Turkish relations and de-emphasis of Iraq in U.S. strategic planning led to an ambivalent position on the PKK, in which the U.S. formally opposed, but tactically tolerated, PKK operations in northern Iraq. This third phase included a spike in U.S. counter-PKK support following a bilateral crisis in 2007-2008, which may have contributed to a period of extended negotiation. A fourth phase began after the U.S. intervention in Syria in 2014 against (ISIS), during which it decided to rely upon the PKK-affiliated YPG as a ground force to confront ISIS in lieu of a larger U.S. force deployment. As of late 2023, the U.S. remains committed in terms of financial and operational support to a group disavowed by its top-level counter-terror policy commitments - through the expedient ignoring of extensive evidence of close ties between the YPG and senior PKK leadership. This contradiction will only be resolved when U.S. forces exit Syria, where they are entirely dependent upon the YPG for local security. In the meantime, the strain caused in U.S-Turkish bilateral relations by support for an FTO affiliate will remain a policy challenge.

2.1. 1984-1996

Washington avoided clear commitment or engagement regarding the PKK. Washington focused more policy attention on the conflict between Kurds in Iraq and Saddam Hussein’s regime than on the PKK’s campaign against Türkiye in the late 1980s and early 1990s, which is to say the PKK’s first decade of active terror and guerilla operations. During this period Washington continued close defense industrial cooperation with Ankara, and publicly supported the Turkish right to self-defense against PKK attacks. Yet, the U.S.-led Operation Provide Comfort (OPC) provided PKK forces the ability to establish bases in Iraqi Kurdistan near the Turkish border, by virtue of preventing Iraqi military forces from operating in the north of the country. This would lead to a series of Turkish incursions targeting PKK bases, beginning in 1991.[iii] After initially tacitly accepting the 1995 Turkish military operation against PKK bases in northern Iraq, senior U.S. officials called on the Turks to withdraw, and hinted at neutrality in the Türkiye-PKK conflict.[iv] Operation Provide Comfort generated increasing sympathy for Kurds in the U.S., and suspicions of Turkish intentions involving Iraqi Kurdistan contributed to American reticence to unambiguously support Turkish efforts there against the PKK.[v] In 1994, Congress withheld military loans to Türkiye until the Executive Branch submitted a report on alleged human rights violations by the Turkish government in its campaign against the group.[vi]

2.2. 1996-2003

The U.S. provided direct and active support to Turkish actions against PKK. The Clinton Administration shifted during its second term to a less ambiguous and more supportive position on Turkish security concerns. During this period, the U.S. continued its role as the major supplier of arms and equipment to the Turkish military.[vii] In 1997, the State Department complied with Turkish requests to formally designate the PKK a Foreign Terror Organization.[viii] The Clinton Administration declined to criticize cross-border operations by Turkish forces into northern Iraq on several occasions between 1995 and 1998, and participated in a diplomatic process with the Turks to achieve a ceasefire between the two major Kurdish groups (KDP and PUK) and pledge both to resist encroachments by the PKK.[ix]

With strong backing from the U.S., Ankara pressed neighboring governments to restrict PKK activities in their countries. In addition to military operations in Iraq, the Turkish government pressed Syria to expel PKK leader Abdulla Öcalan and PKK training camps, threatening military action if no progress was made.[x] This led to the signing of the 1998 Adana protocol, under which Hafez al-Assad agreed to expel Öcalan, shut down PKK camps, and allow Turkish forces to conduct cross-border counter-PKK operations to a depth of ten kilometers. Iran gave a nod to Turkish concerns by formally cutting ties with the group the day U.S. forces invaded Iraq in 2003.[xi]  In 1999, the U.S. pressured Athens[xii] and other governments that had harbored PKK leadership to stop doing so, and provided intelligence that led to the capture of Öcalan in Kenya - and his subsequent trial and imprisonment in Türkiye.[xiii]

In essence, the U.S. decided to stop the cycle of PKK provocations and Turkish ground incursions into Iraq by providing targeted counterterror assistance - which worked right up until the invasion of Iraq in 2003. In 1999 the PKK declared a unilateral ceasefire, elevated more moderate leadership, and indicated a willingness to pursue Kurdish nationalist aims in Türkiye through political means rather than armed violence. In return, Ankara initiated a series of cultural and political steps that raised hope for a sustained end to terror in the Turkish southeast.[xiv]

U.S. designation of the PKK as an FTO in 1997[xv] was based on its attacks on Turkish security forces, diplomatic and commercial targets, tourists and other civilians.[xvi] While some observers have argued for delisting the group,[xvii] the case for doing so has not been persuasive and the designation has been confirmed numerous times.[xviii] Washington has maintained a consistent official line that it supports the fight against the PKK, despite growing tensions over U.S. partnership with that group’s Syrian affiliate, the YPG.[xix] Due at least in part to U.S. support of Turkish counter-PKK operations and staunch political backing during this period, the PKK had been demoralized and defeated in field operations by the year 2000, withdrawing its remaining fighters on its own accord.[xx]

2.3. 2003-2014

The U.S. military campaign in Iraq led to a modus vivendi with the PKK. With an increasingly difficult occupation of Iraq after the 2003 invasion, U.S. military and intelligence forces provided little or no support to Ankara against the PKK - the Iraqi insurgency and Al Qaeda in Iraq were their sole focus. The U.S. also warned against Turkish incursions, meaning the PKK had a more secure base in northern Iraq than it had in previous decades.[xxi] With the PKK using this to escalate attacks into Türkiye, a new crisis in bilateral relations emerged, as both elite and popular opinion towards the U.S. hardened in Türkiye.[xxii] President Bush met with Prime Minister Erdoğan to find a mutually acceptable resolution, which included new intelligence support, more forceful denunciations of the PKK by Washington, and a green light for renewed - though limited - Turkish operations in northern Iraq.[xxiii] The U.S. also appointed a retired four-star general, James Ralston, as special envoy for cooperation against the PKK.[xxiv]

Renewed, albeit limited, resurgence in U.S. support to Turkish counter-PKK efforts may have helped stimulate the most serious attempt at a negotiated solution to the PKK’s armed campaign, beginning in 2008 with secret talks in Oslo, Norway between representatives of the Erdoğan government and the PKK. In fact, both episodes of the U.S. demonstrating solidarity with Ankara in its counter-PKK efforts - the late 1990s culminating in the capture of Öcalan, and 2007/2008 - resulted in serious peace talks. Convinced that it could not defeat the Turkish military and lacking the sponsorship of a global power, the PKK changed its political program in the early 2000s to shift from an independent Kurdish state to changing the nature of the Turkish state.[xxv] The AKP changed political narratives about the Kurdish issue in Türkiye, lifting many taboos and implementing serious reforms. Discrete negotiations ensued, first with Turkish intelligence engaging the PKK and then with increasingly senior confidantes. The point of these talks was to shift from the securitized approach to conflict termination and seek a political settlement.[xxvi]

By 2009 these exploratory talks matured into the “Kurdish Opening,” an increasingly public dialogue and discrete set of negotiations in pursuit of a political settlement.[xxvii] The process seemed close to ultimate success by March of 2013, when Öcalan issued a call for withdrawal of PKK fighters from Turkish territory and a shift to political struggle.[xxviii] Yet the government and PKK negotiating positions on structural change within the state proved irreconcilable, and the PKK built up new fighting units and infrastructure in the cities of southeast Türkiye.[xxix] During the period of the Kurdish Opening - also referred to sometimes as the “Solution Process” - Öcalan and other key PKK figures retained revolutionary violence and armed actions in Türkiye not only as an alternative to negotiations, but as a necessary complement to them. Given the group’s growing military power and international support in Syria beginning in 2014, the leadership felt they had better options than concessions and an end to the conflict with Türkiye.[xxx]

By late 2014 the PKK’s Syrian affiliate, the YPG, had developed a proxy relationship with U.S. forces fighting ISIS in Syria[xxxi], emboldening PKK fighters in Türkiye to resume combat operations. The rapid turn of fortunes for the PKK regionally - international sympathy, new recruits, U.S. air and logistical support, control of territory in Syria - convinced Ankara that the PKK was deepening, rather than abandoning, its military campaigns and territorial ambitions.[xxxii] The U.S-YPG relationship was initially presented by Washington as one of necessity (temporary, tactical, and transactional)[xxxiii], but fostered soaring rhetoric and deepening implied commitment.[xxxiv] Given the tepid nature of previous U.S. commitments to countering the PKK, the readiness of Washington to partner with the PKK’s Syrian affiliate, and the strengthening of the YPG (and by extension the broader PKK) as a result of U.S. sponsorship, signalled that a clear change in dynamics was underway.

2.4. 2015-present

In 2013 and 2014, with the Kurdish Opening in progress, leaders in Ankara felt unease but little direct risk as thousands of PKK-aligned fighters from Türkiye, Iran, and Iraq traveled to Syria to help the YPG wrest territory from the anti-Assad opposition and defend it against ISIS fighters. Concerns became far more intense as it became clear that events in northeast Syria were leading to a surge in pan-Kurdish sentiment across the region, lionization of the group in the Western press, plus territorial and political control unprecedented in the history of the PKK’s various franchises.[xxxv] After ISIS’ rapid territorial gains during 2014 - and spectacular killings of American hostages - the Obama Administration became desperate to partner with a local force that would oppose ISIS without requiring large numbers of U.S. ground forces. Despite connections to the broader PKK FTO network, the YPG seemed the most efficient option for Washington.[xxxvi] During the late 2014 ISIS siege of Kobane, Ankara declined to intervene on behalf of the Kurdish forces and the U.S. decided to do so. The decision to partner with the YPG despite Ankara’s concerns about the disintegrating peace process with the PKK - and the concurrent dramatic increase in PKK capabilities due to U.S. support - ended prospects for U.S.-Turkish cooperation in Syria and marked a significant new source of tension in the bilateral relationship. To Washington however, it seemed strategically sound, and the costs manageable.[xxxvii]

The U.S. began a Train and Equip program for the YPG, later re-designated the Syrian Democratic Forces or SDF, that entailed the deployment of top-tier U.S. special forces advisors, air and logistical support, and funding under the Counter Terrorism Train and Equip Fund (CTEF) of more than $100 million per year.[xxxviii] Collaboration with the SDF enabled the U.S. to end Islamic State control in northeast Syria[xxxix] - though the Turks themselves had cleared ISIS forces from west of the Euphrates with their own military operations in 2016.[xl] Yet it did not result in the “enduring defeat” of ISIS, as small terror actions continued while tens of thousands of ISIS-affiliated prisoners remain still in a network of SDF-run detention facilities in northeast Syria.[xli]

Turkish concern about the open-ended U.S. military partnership with and subsidy of PKK-affiliated forces in Syria has evolved into a broadly-held view among political and security elites in Ankara that the U.S. is consciously and indefinitely nurturing a threat to its NATO ally.[xlii] One response to this has been a series of additional military campaigns in northern Syria - Olive Branch (2018), Peace Spring (2019), and Spring Shield (2020) - to establish a secure corridor or “safe zone” that keeps both Assad and PKK-aligned forces away from much of the Turkish border.[xliii] Together with operations in Iraq in coordination with the Iraqi Kurdish forces aligned with the Erbil-based Kurdistan Democratic Party (KDP),[xliv] these operations have resulted in a broad zone of Turkish military operations that will almost certainly stay in place until the U.S.-PKK arrangement ends, and PKK military capabilities are attenuated. Washington seems locked in to a military arrangement without an end state or political goal, which means the U.S. and Türkiye are in a sort of proxy cold war in Syria with no end in sight.[xlv]

In fact, the stalemate in northeast Syria may bring even sharper tensions in the US-Turkish bilateral relationship in coming years. The massive train and equip program for SDF/YPG shows no signs of significant reduction, with funding secure into the foreseeable future.[xlvi] Indefinite sponsorship continues despite that the ideology, strategic approach, and tactical relationships of the YPG and its controlling PKK headquarters in the Qandil mountains of Iraq threaten not only NATO ally Türkiye, but Kurdish rivals such as the U.S.-allied KDP.[xlvii] Yet U.S. forces have gone beyond merely working with the SDF in Syria, and have begun transporting SDF elite units and political leaders into Iraq and beyond, with no declared policy from Washington to explain why.[xlviii] The SDF has also faced significant uprisings among tribal elements in the majority-Arab areas it exercises de facto control over. The current stage of U.S. policy towards the PKK is thus one in which the PKK, supported by Iran and the U.S., maintains some territorial control in both Iraq and Syria, remains politically marginal in northern Iraq and Türkiye, and faces sustained military pressure, all of which ensures its dependence on American support - as well as a deficit of regional political legitimacy that has no apparent remedy.[xlix]

Over the four decades from 1984 through 2023, then, U.S. policy toward the PKK has shown great variability, as has the behavior of the PKK in responding to policy change. The PKK has conducted ceasefires and negotiations after periods of significant counter-terror operations by Turkish forces and/or U.S. support of such operations in 1993, 1998-99 and 2007-08. The first of these negotiating interludes ended with the death of Turkish President Turgut Özal. The latter two ended after major U.S. military moves that impeded Turkish freedom of military action south of its borders with Iraq and Syria - Operation Iraqi Freedom in 2003, and the commitment of U.S. airpower, logistical support, and advisors to YPG forces in 2014. On a regional level, U.S. efforts to curtail central government control over northern Iraq and northeast Syria led to growing PKK control over large parts of these regions. U.S. policy has thus had the contradictory effect of supporting Turkish efforts to suppress PKK within Turkish territory, while strengthening the group’s capabilities and its search for political legitimacy elsewhere.

  1. Effect on the U.S.-Turkish Alliance

In each phase and shift of U.S. policy, it is possible to discern motives of pragmatism rather than principle or declared counter-terror policies. From 1984 through 1996 the U.S. demonstrated no interest in making the PKK an American problem, preferring to leave it to regional diplomacy and power politics.[l] Concerns in Western capitals over the PKK centered as much on concerns about human rights violations by Turkish security forces as they did on the group as a terror phenomenon, yet geopolitical considerations led to avoidance of either helping or opposing Turkish counter-PKK efforts.[li] Washington’s professed commitment to humanitarian concerns and protecting Kurdish civilians was increasingly seen in Ankara as tacit consent and occasional direct support to PKK elements based in northern Iraq and Türkiye.[lii] In 1994 the U.S. Congress stipulated that further military loans to Türkiye would require a report on alleged human rights violations by Turkish security forces during counter-PKK operations.[liii]

From 1996-2003, elevated support for Türkiye against the PKK reflected a need for Turkish support in the Balkans, on Iraq, in Afghanistan and elsewhere - a PKK policy based on a quid pro quo for Turkish support in other conflicts. It also coincided with the advent of triangular cooperation (Türkiye-Israel-U.S.) and the narrative of a “strategic partnership” that was reshaping the Middle East.[liv] From 2003-2014, the U.S. sought to deter major Turkish military operations against the PKK in Iraq, but acceding to limited operations after PKK attacks became intolerable to Ankara.[lv] The post-2014 arrangement with the YPG stemmed from the disinclination to use U.S. ground troops, the preference to conduct counter-terror operations using local proxies without being responsible for political outcomes (the so-called By-With-Through operational approach), and the fact that Washington could not come to any consensus on the Syrian mess other than defeating ISIS.[lvi] Washington opted for the very pragmatic - and in terms of intra-alliance relations, extremely problematic - course of instrumentalizing an FTO offshoot (YPG) to fight another FTO (ISIS) despite linkages of ideology, personnel, and strategic guidance to the parent organization (PKK) still fighting a treaty ally (Türkiye).[lvii]

Such pragmatism operates in tension with the logic of alliance. U.S. security experts and officials, including the current Secretary of Defense Lloyd Austin, have long maintained that the key strategic advantage of the U.S. against potential rivals is its network of alliances.[lviii]  The consensus components of alliance systems are the pooling of military resources, and mutual support against external threat to an alliance member.[lix] American pragmatism regarding the PKK demonstrates a failed alliance in this regard, dysfunction that predates accusations that Ankara has become a “bad ally” in recent decades.[lx] Many observers have noted that non-alliance “alignment” relationships incur more limited and contingent obligations, and are more common in the current era than true alliances. The U.S. policy of ignoring Turkish threat assessments and security concerns coincides with scholarly literature questioning the relevance of formal treaty mechanisms in the 21st century.[lxi]

The larger partner in a security relationship or alliance may have the luxury of double standards, but middle-sized partners have options of their own. Ankara has responded to the strategic alienation and mutual antagonisms stemming from U.S. PKK policy - reinforced by an enduring search for strategic autonomy beyond the PKK issue - through a number of hedging and balancing strategies. These have included local cooperation with Russia and Iran, deepened security relationships with non-NATO states such as Ukraine and Azerbaijan, and an expanding set of diplomatic and economic partners globally.[lxii] Ankara has also sought to change the asymmetric nature of power relations between itself and Washington by developing independent power projection capabilities including unmanned combat systems, precision munitions, regional defense agreements, and more agile civil-military relations.[lxiii] The following section will examine how Ankara has responded to the evolution of the U.S. PKK policy, and the current dynamics likely to follow from this response in the coming years.

  1. An Expert Cross-Section

How do long-time observers of the U.S.-Turkish relationship who have closely followed the vicissitudes of U.S. PKK policy and Turkish counter-PKK strategies assess the current impact on bilateral relations? With minor differences, a half-dozen such experts[lxiv] reflected several common themes in responding to questions about the salience of U.S. YPG/PKK support to bilateral relations; whether the YPG has autonomy or can be separated from the PKK; the long-term impact of the impasse over the YPG/PKK; and how critical a turning point in bilateral relations occurred with the 2014 U.S. decision to train, equip, support, and ultimate arm the YPG. In each case, the responses indicate a long-term structural impediment to improved, or even functional, alliance relations, and reinforce the centrality of U.S. PKK policy as a problematic aspect of bilateral relations. On how to characterize the U.S.-PKK relationship:

Whereas US help in capturing Öcalan had strengthened the sense of appreciation in Türkiye, the US's subsequent reluctance to help Türkiye in eliminating PKK targets in Northern Iraq and, worst of all, the artificial distinction it began to make between PKK elements in Syria and its mothership, eroded that trust and led to a deep sense of resentment that has now permeated Turkish society. The US continues to underestimate the destructive impact of this on Turkish-US relations.

The relationship continued due to USCENTCOM transforming from a policy-implementing entity into a policy-making entity. As the White House did not develop a policy for Syria, USCENTCOM did its own thing and exceeded its legal framework in Syria. The US relationship with the PKK is a product of USCENTCOM and a disinterest of the White House in Syria.

We can define what the US relation with the PYD is not: temporary, transactional or tactical as U.S. officials claim. The pretext of the PYD/YPG being the local actor to defeat the common threat of ISIS is not a credible argument. ISIS was a common threat to all at the global scale, but the PYD/YPG together with the PKK/HPG is the common threat to all at the regional scale. U.S. relation with the PYD is a replacement of the ISIS threat with PYD/YPG threat by downgrading the threat level from global sale to regional scale.

On whether there is a substantive difference between the YPG/PYD and broader PKK:

The facts say otherwise. Of course, there was a time when Türkiye itself had engaged the PYD. But that doesn't change the fact that they (both the PYD and the YPG) are affiliated with the PKK. That slogan (temporary, tactical, transactional) never resonated with Ankara and is so stale that it adds insult to injury. It was a bad excuse for a selfish US decision to make an exception in the fight against terrorism, at Türkiye's expense.

The YPG is not a suitable partner for this new period to eliminate ISIS. The YPG may have had an interest in fighting against ISIS, but they don’t have an interest in extinguishing their sole source of legitimacy as well. The YPG is interested in keeping ISIS alive without letting it become a real threat.

In today's world, nothing remains secret. The public knows that the USA continues this relationship knowing that the YPG is an organic part of the PKK. This relationship not only creates moral problems in the relations between the USA and Türkiye, but also poisons other relations. The USA is clearly at odds with its own value system. The perception of the United States among the Turkish public is untrustworthy, selfish and hostile.

On how the perception of U.S. support to the YPG/PYD and, by extension, the PKK affects Turkish views of the longer-term relationship:

Türkiye's main national security concern continues to revolve around the PKK and its offshoots. In that sense, US policy on these issues will be among the main drivers of the Turkish-US partnership.

The American partnership with the YPG is seen as a direct threat to Türkiye. Most Turks believe that the end target is Türkiye. For Turks, the PKK is the single most important threat across the political spectrum. The US support for them poisons the relationship way more than Washington thinks. Anti-Americanism is on the rise in Türkiye. In any public TV debate about relations with the US, Eurasianists win within the scope of minutes. They refer to the American support of the YPG, and the debate ends. Many Turks believe that the US destroyed Iraq and Syria and that Türkiye is next.

The PKK (and the PUK) owe their organizational survival and growth to Iran, historically. Now, the US is promoting the PYD/YPG to help combine the capacity and capability of Iranian proxies so that Iran would easily instill its influence in Syria and Iraq with a more advantageous regional context.

How big a turning point was the 2014 U.S. decision to support the YPG, in terms of bilateral relations?

It had two major destructive implications. First, it was a blow to bilateral Turkish-US relations and continues to severely hemorrhage it. Second, it had destructive implications within NATO. Coupled with its national policy shift, the US also spearheaded the same approach within NATO and effectively nurtured a bloc within the Alliance against Türkiye, leading to a vicious cycle that came at a cost to NATO's resilience.

Many foreign policy and security decisions of Türkiye can be explained by the US support to the YPG in 2014. Turkish decision-makers lost their trust in the US and have made several other political decisions in response to the American support of the YPG. For example, the acquisition of the S-400 air defense system from Russia would not have occurred if the US had not partnered with the YPG.

All aspects of the bilateral relationship with the US are viewed from the prism of the US partnership with the YPG.

The Syrian revolutionary movement suffered a major set-back and many of them either leaned towards ISIS or Heyet Tahrir al Sham (HTS now, Jabhat al-Nusra at that time) (…) the PKK/HPG was influenced by the PYD/YPG’s grip over US support and the PKK ended the ongoing solution process in 2015 and waged a renewed terror campaign in the form of an uprising in urban cities in eastern Turkish cities. Discrepancy between US and Turkish …also allowed Russia and Iran to get involved in the Syrian Civil War more actively in 2015. As the revolutionary movement weakened, the PYD/YPG increased its influence and they posed more threat to Türkiye… weakened NATO collective defense…and may have even encouraged the 2016 coup attempt in Türkiye.

  1. Turkish Responses and Current Dynamics

U.S. policy towards the PKK has had major shifts and a unique evolutionary path. So too has the Turkish approach to counter-PKK tactics and strategy. As the PKK shifted first from rural to urban insurgency on Turkish soil from bases in Iraq and Syria, then to control over areas in Iraq and Syria, Turkish efforts moved from domestic counterterror operations to eliminating PKK control of border areas. Sympathetic Western observers counseled the PKK in Syria to avoid conflict with Türkiye and focus on local administration in an attempt to preserve its gains, but the twin realities of a YPG whose value lies in fighting prowess rather than political legitimacy and the continuing political control exercises by foreign PKK cadres prevented real evolution or compromise.[lxv]

Turkish counter-PKK strategies from 1984 to the present have relied on a mixture of elements.[lxvi] These have included security operations within national borders by police, intelligence, military, and “village guard” forces; diplomatic campaigns to neutralize foreign pressure on Ankara and external support to the PKK; co-optation and alliances with conservative Kurds; political and economic reforms; direct negotiations; and increasingly effective cross-border military operations and precision strikes against PKK leadership. During the period of AKP rule (2002-present), the early emphasis was on reforms coupled with continued “brute force” military operations. From 2009-2013, negotiations and restraint in the use of force was attempted. Since the collapse of negotiations and the advent of direct U.S. support to the YPG, Ankara has relied on dramatically enhanced military technical capabilities to move the fight off of Turkish territory and to go after PKK bases, infrastructure, and personnel in Iraq and Syria.[lxvii] The U.S. has adapted in turn to this increasingly forward posture by tacitly accepting Turkish operations, while warning against significant escalations and insisting on due protection for U.S. forces in the region.[lxviii]

This cycle of evolving U.S. policy and Turkish response has produced five key dynamics that will shape the next several years of Türkiye’s counter-PKK efforts and greatly influence bilateral relations. The first is sustained proxy conflict between the U.S. and Türkiye in Syria. American commitment to the By-With-Through operational approach in northeast Syria prompted the Turkish “Safe Zone” strategy, and the continuation of both ensures sustained future conflict and mutual mistrust.[lxix] By-With-Through triggered this response by supporting local governance structures linked to the U.S.-subsidized proxy force - the YPG - as presumptively local and legitimate, without real scrutiny or compromise to sensitivities of other local actors and in willful disregard of the YPG’s close ties to the PKK. The de facto administrative structure organized by the PKK’s Syrian political wing (the PYD) is referred to as Autonomous Administration of Northeast Syria (AANES), and it claims authority over areas controlled by the Turkish-supported Syrian Interim Government (SIG)[lxx]. Unquestioned U.S. support has obviated the need for genuine political compromise between the AANES and various groups in northeast Syria.[lxxi] U.S. spending in support of YPG/PYD control[lxxii] militates against political stabilization of the area, and virtually assures future conflict with other local actors (including those supported by the Turks). Until the U.S. develops an alternative political strategy to unquestioned YPG/PYD control of Northeast Syria via the AANES - or until the AANES collapses or is re-absorbed by the Assad regime - this dynamic will persist.

The second dynamic is the continued ascendance of the YPG as the most effective and prominent node of the regional Öcalan movement.[lxxiii] The YPG is currently the highest-profile franchise in the PKK broader network - the only place where PKK ideas have been put into practice on a regional scale - but remains constrained by political leadership of the movement at Iraq’s Qandil mountain complex and elsewhere.[lxxiv] Ironically, the Kurdish demographic base is much thinner in Syria than in either Iraq or Türkiye, and thus the Kurd-based revolutionary movement rests on the most tenuous, and externally-dependent grounds. Yet YPG leadership has expressed aspirations to become a “national army” with 100,000 fighters, which would presumably entail a power shift within the PKK from northern Iraq to northeast Syria.[lxxv] U.S. military officials have attempted to extend the group’s reach regionally by escorting YPG fighters to joint training with PUK forces in Iraq’s Sulaymaniya,[lxxvi] and facilitating the travel of top commander Mazloom Abdi to meetings in Abu Dhabi.[lxxvii] Similar to the first dynamic, this will continue as long as U.S. presence alongside and subsidy to the YPG/PYD keeps flowing.

The third dynamic is the increasing capability of the Turkish defense industry to not only meet domestic demand for affordable, high-quality arms and equipment, but to export to an expanding network of trusted allies and defense partners, both within NATO and outside it.[lxxviii]  The Turkish defense industry has become a global leader, and has reached a “critical mass” of engineering and systems integration experience to develop new technologies with or without Western approval. This has mitigated the longstanding threat of erstwhile arms suppliers in the West who sought to constrain Turkish counter-PKK and other military actions through restrictions on defense exports.[lxxix] Combined with an effective operational approach bringing together unmanned reconnaissance and strike systems, manned aircraft, precision munitions, ground maneuver forces, local proxies, and agile security decision-making, Turkish industrial advances have more or less driven the PKK from the field within Turkish borders - and exacted an increasing toll on the PKK beyond them.[lxxx] This dynamic seems likely to continue as long as the PKK and its affiliates maintain an armed presence along or near those border. Under conditions of relative advantage for Turkish forces - whose losses in counter-PKK operations are proportionally far less than those of the militants - a military solution or effective suppression likely will continue to hold more appeal than new negotiations.[lxxxi]

The fourth dynamic is sustained and manifest tension between the KDP and PKK in northern Iraq as U.S. support emboldens, and Turkish counterterror operations squeeze the latter. The Erbil-based KDP has faced pressure from Tehran, Baghdad, and the rival PUK in recent years, with the former seeking to restrain Kurdish autonomy and the latter trying to wrench control of it from the KDP.[lxxxii] Tacit coordination among those KDP opponents has pressed the Barzani leadership, adding even more value to the alignment with Ankara.[lxxxiii] Ankara and Erbil share in interest in limiting PKK influence in northern Iraq. This applies to the YPG in Syria, as well, which has marginalized and suppressed activities of the KDP-aligned Kurdistan National Congress (KNC).[lxxxiv] The complex competition for influence among the PKK/YPG, PUK, and KDP is exacerbated by opposing and sometimes contradictory efforts by Baghdad, Tehran, Washington and Ankara to influence its outcome.[lxxxv] For the KDP, U.S. efforts to maintain or grow PKK/YPG power pose no less of a security concern than they do for the Turks; the U.S., through a combination of inattention, inertial support to the PKK, and naivete regarding the results of the KDP-PUK rivalry is on the brink of ceding the region to Tehran.[lxxxvi] The fragility of the situation in Iraqi Kurdistan may be the most dangerous dynamic in the entire PKK-Türkiye-U.S. network of issues, as it threatens to reverse three decades of progress for U.S. Kurdish policy in Iraq with no clear political gain to offset.[lxxxvii]

The fifth and final dynamic is the gradual diminution of U.S. rationale for supporting the PKK’s Syrian franchise, as the raison d’etre (ISIS) fades further from public consciousness. All U.S. authorities and funding for operations in Syria stem from the threat of ISIS.[lxxxviii] Yet the Caliphate was removed in early 2019, and the concept of “enduring defeat” for an enemy that controls no territory and no longer launches major operations decreases over time, as domestic critics have noticed.[lxxxix] U.S. defense and policy experts generally recognize that the presence of U.S. forces in Syria - and thus their relationship with the PKK-affiliated YPG - has outlasted the ISIS-rooted justification.[xc] As conflicts in Ukraine, Gaza, and elsewhere eclipse the ISIS campaign in Syria - and as the Islamic State itself shifts operational focus to Africa - the link between U.S. interests and the PKK in Syria has attenuated.[xci] There may be valid reasons for the U.S. to keep troops in Syria - deterring Iran, constraining Russia, not giving Assad a free pass - but they have little to do with the legal and strategic rationale for partnering with the YPG and by extension the PKK, and cannot demonstrably provide returns worth the risk of antagonizing NATO ally Türkiye.

The aggregate effect of these five dynamics has been initial satisfaction of urgent counter-Islamic State goals followed by mounting complications and costs with no easy off-ramp. U.S. assistance increased YPG/PKK capabilities and political influence in Syria and Iraq, but these were reduced in turn by Turkish offensives against what Ankara perceived as an emerging “terror corridor.”[xcii] The operational capabilities and reach of PKK forces plateaued, and they have lost considerable territory, retaining far too little to be self-sustaining without U.S. support. A legacy ISIS movement survives in the prison camps and rural hinterlands of northeast Syria. Meanwhile, Iranian threats to U.S. allies in the Gulf and Israel have spilled over into threats on U.S. installations in Iraq and Syria.[xciii] In short, the PKK policy, enmeshed as it has been with Iraq and Syria policy, now represents an eroding position with increasingly shaky strategic logic and increasing risks.

  1. Projected Scenarios out to 2030

The stalemate that emerged from evolving U.S. PKK policy, Turkish responses, geopolitical and other regional dynamics will persist until one or more significant variables change. A short list of variables with considerable potential to reshape dynamics might include the following:

  • Fundamental shift in U.S. Syria policy toward withdrawal of forces and ending the YPG proxy relationship (possibly after the 2024 Presidential elections)
  • Failure of SDF/YPG control over northeast Syria as a result of actions by Sunni tribal groups, Assad regime forces, Iranian proxy forces, or Turkish forces
  • A significant incident involving U.S. casualties in Syria
  • A political deal between Damascus and the YPG/PYD
  • A return to negotiations between the Turkish government and PKK
  • Emergence of a stable governance model in northeast Syria that achieves legitimacy with Arab tribes, non-YPG/PYD Kurds, the KDP, and Ankara.

The last three of these six appear implausible as of early 2024. There have been multiple rounds of negotiations between the YPG and Damascus, but no indication that Assad has any intention of meeting the other side’s demands.[xciv] Turkish security experts have made clear that there is no current or projected appetite in Ankara for renewed political dialogue with the PKK movement.[xcv] As for reform of the AANES into something more palatable and pluralistic, precious few observers who know the YPG/PYD first hand believe that it can or will share power in any substantive way.[xcvi]

The first three all are plausible, and each would likely lead to the end of the status quo altogether and collapse of the AANES. President Trump tried to pull out of Syria twice, and will likely mount a third attempt should he win election in 2024 - and other Republican candidates may do the same.[xcvii] Arab uprisings against the Kurdish-dominated AANES and SDF in 2023 did not fundamentally damage YPG control, but may escalate in the future.[xcviii] Absent an explicit strategic or political goal for the current U.S. deployment in support of the YPG, it is hard to imagine that it would continue if significant casualties are incurred.[xcix] The bad news for Washington is that all of these plausible changes would mark the collapse of its current Syria and ISIS strategies. The silver lining is that they would also remove the de facto subsidy to an FTO (the broader PKK movement,) and remove a key irritant in bilateral relations with Ankara.

Depending on how these variables play out in the coming months and years, several scenarios are possible for the U.S. presence in Syria and the related impact of U.S. PKK policy on the U.S.-Türkiye relationship. The first would be a deliberate reduction in U.S. presence and support to the YPG accompanied by negotiations with Ankara, YPG leadership, and (indirectly) Damascus to achieve a modus vivendi that reduces the likelihood of new military actions by any of them in northern Syria. Ankara has already been in touch with Damascus to discuss acceptable parameters for such a process.[c] A second scenario would be an abrupt collapse of the AANES and departure of U.S. forces without such an arrangement. A third scenario would be success in the U.S. experiment to forge a form of “Kurdish unity” that anchors the AANES to the KRG.[ci] A final scenario would be the continuation of the current status quo - U.S. amid deteriorating political conditions and increasing Iranian-backed pressure in both Syria and Iraq. The later seems analogous to U.S. relations with the Sahwa (Arab Uprising) forces in Iraq in from 2008-2011 and to Afghan forces from 2017-2021 - support of military forces within the context of a diminishing strategic logic.

Under the most likely scenarios, the YPG - and thus the broader PKK movement - will retain residual sympathy in Washington, and some level of military support, in the coming years.  Consequently, deep mistrust between US and Turkish policy elites will likely also continue. Ankara will continue to feel a need to balance and hedge against U.S. approaches in Iraq and especially in Syria, hindering collaboration in stabilizing the region and in broader strategic cooperation.

  1. Conclusion

The foregoing analysis has established that U.S. PKK policy has negatively influenced bilateral relations, leading both to low trust in Ankara and consequent Turkish policy responses that erode trust and sympathy in Washington, as well. The trajectory of this policy over the periods examined has undermined faith in mutual security commitments, and contributed to a highly transactional bilateral relationship with little “feel” of a sincere alliance. This fundamental problem of coordination and cooperation persists to the present day.

A second central finding is that U.S. policy has lacked cohesion or unity of principle over time. During each period of U.S. policymaking with regard to the PKK, there has been a degree of pragmatism that makes each incremental decision or shift understandable on its own terms. Taken as a whole however, the shifts comprise a pattern of inconsistency that undermines long-term interests such as alliance solidarity and conflict resolution. The U.S. has conducted a Global War on Terror, meticulously maintains a list of Foreign Terror Organizations (FTOs), and routinely adds terror designations for those related to FTOs in a secondary or sometimes tertiary manner. Yet it has shown a willful ignorance regarding the palpable - and regionally acknowledged - intimate connections between the YPG/PYD and the broader PKK movement. This mindset has not upheld the U.S. policy position anywhere but in Washington - it is generally perceived by Turks, Kurds, Arabs and others as a proverbial wink and nod at its own terror listings. More broadly speaking, the variability of the U.S. approach to the PKK over time in the context of an alliance relationship may give reason for U.S. partners and treaty allies to doubt the sincerity of U.S. security guarantees. The U.S. has walked away from allies in Afghanistan and convinced Mideast allies it is ambivalent to the Iran threat, but the maneuvering regarding the PKK predates both of these as an indication that it protects allies at its own convenience.

A third conclusion that emerges from the analysis is that time, so to speak, favors the Turks. The growth of Turkish power projection capability and defense industrial resources, coupled with a shift in Turkish strategic culture towards a more independent and autonomous mode, has lowered the barriers and costs associated with Turkish action against the PKK. The growing network of Turkish defense and security partners, plus Ankara’s leverage within NATO, greatly reduces the threat of international pressure against Türkiye to soften its approach to the PKK. With the U.S. seeking to avoid wars and military commitments in the Middle East, the tenuous position of the PKK regionally - and the YPG/PYD in Syria specifically - will likely become more acute over time. Policy returns for the U.S. seem destined to shrink and turn negative.

A major caveat pertains to these conclusions. The PKK/YPG/PYD is not the only problem in the bilateral relationship. U.S. policy decisions regarding the group have had a clear negative impact on bilateral relations, but there are other issues. From the Turkish side, these include U.S. Mideast policy, especially regarding Israel and Palestine; U.S. failure to expel or prosecute Fethullah Gülen for his alleged role in the coup attempt of 2016; a de facto arms embargo reinforced by anti-Turkish lobbies in Washington; and a general failure to recognize Türkiye as an equal partner. For Washington, concerns over Turkish animosity with Israel and Greece, the perceived democratic deficit in Türkiye, and the view in Congress that Erdoğan’s Türkiye has become generally anti-Western contribute to the lack of trust. Even if the respective views and approaches to the PKK became more compatible, these other frictions would remain.

Yet no issue mobilizes the Turkish public, and Ankara’s policy elites, quite like U.S. support for the PKK. For scholars of policy and international relations, as for practitioners, it is important to understand the centrality and durability of this issue to bilateral relations. It presents a unique and thorny case for scholars working to understand low-trust relationships, transactionalism, and incrementalism in foreign policy. For the respective policy communities in Washington and Ankara, the analysis presented in this paper may provide context, framing, and assessment of dynamics helpful in managing further evolution of U.S. PKK policy. A shift from policy incrementalism to non-incremental change - in this case, a shift back away from PKK-tolerance or instrumentalization - is more likely in later stages of a policy “life cycle,” and the Syria/ISIS policy may well be in such territory.[cii]


[i] Christer Pursiainen and Tuomas Forsberg, “Relations of Trust and Mistrust,” in The Psychology of Foreign Policy (New York: Palgrave MacMillan, 2021), 299-336.

[ii] Galib Bashirov and Ihsan Yılmaz, “The Rise of Transactionalism in International Relations: Evidence from Türkiye’s Relations with the European Union,” Australian Journal of International Affairs 74, no. 2 (2020): 165-184.

[iii] Anıl Karaca, “Disrupting Terrorist Networks: An Analysis of the PKK Terrorist Organization,” M.A. thesis, (U.S. Naval Postgraduate School, 2010), 38-39. https://apps.dtic.mil/sti/citations/ADA536525

[iv] Lally Weymouth, “We Can’t Be Neutral on Türkiye,” Washington Post, April 2, 1995. https://www.washingtonpost.com/archive/opinions/1995/04/02/we-cant-be-neutral-on-turkey/ca7bc20b-b38d-4d2a-8b21-b0a91a8225fc/

[v] George D. Kramlinger, “Chapter 3: Operation Provide Comfort,” in Sustained Coercive Air Presence, (Maxwell, AL: Air University Press, 2001), 19-39.

[vi] Jim Zanotti and Clayton Thomas, Türkiye, the PKK, and U.S. Involvement: A Chronology (Washington, DC: Congressional Research Service, 2019). chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://crsreports.congress.gov/product/pdf/IF/IF11380.

[vii] Stephen Zunes, “The United States and the Kurds: A Short History,” Common Dreams, October 26, 2007. https://www.commondreams.org/views/2007/10/26/united-states-and-kurds-brief-history.

[viii] Ibid.

[ix] Brigitte Hugh, “Perpetuating Peace: Context Versus Contents of Power- Sharing Agreements Between the KDP and PUK of the Kurdistan Region of Iraq in 1992 and 1998,” M.S. thesis, (Utah State University, 2020), 49-55. https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=8964&context=etd.

[x] Alan Makovsky, “Defusing the Turkish-Syrian Crisis: Whose Triumph?” Washington Institute, February 1, 1999. https://www.washingtoninstitute.org/policy-analysis/defusing-turkish-syrian-crisis-whose-triumph.

[xi] Soner Cagaptay and Tyler Evans, “The End of Pax Adana,” Washington Institute, August 25, 2012. https://www.washingtoninstitute.org/policy-analysis/end-pax-adana.

[xii] Miron Varouhakis, “Greek Intelligence and the Capture of PKK Leader Abdullah Öcalan in 1999,” Studies in Intelligence 53, no. 1 (2009): 1-7.

[xiii] Tim Weiner, “U.S. Helped Türkiye Find and Capture Kurdish Rebel,” New York Times, February 20, 1999. https://www.nytimes.com/1999/02/20/world/us-helped-Türkiye-find-and-capture-kurd-rebel.html.

[xiv] Soner Cagaptay, “The PKK’s New Offensive: Implications for Türkiye, Iraqi Kurds, and the United States,” Washington Institute, June 25, 2004 https://www.washingtoninstitute.org/policy-analysis/pkks-new-offensive-implications-Türkiye-iraqi-kurds-and-united-states.

[xv] John Rollins, Foreign Terrorist Organization (FTO) (Washington, DC: Congressional Research Service, 2023). https://crsreports.congress.gov/product/pdf/IF/IF10613.

[xvi] Office of Counterterrorism, “Background Information on Foreign Terrorist Organizations,” U.S. Department of State, October 8, 1999. https://1997-2001.state.gov/global/terrorism/fto_info_1999.html#pkk.

[xvii] David Phillips and Kelly Berkell, “The Case for Delisting the PKK as a Foreign Terrorist Organization,” Lawfare, February 11, 2016. https://www.lawfaremedia.org/article/case-delisting-pkk-foreign-terrorist-organization.

[xviii] Office of the Spokesperson, “State Department Maintains FTO Designation of the PKK,” U.S. Department of State, March 1, 2019. https://tr.usembassy.gov/state-department-maintains-foreign-terrorist-organization-fto-designation-of-the-kurdistan-workers-party-pkk/; Bureau of Counterterrorism, “Executive Order 13224,” U.S. Department of State, September 23, 2001 (November 2023). https://www.state.gov/executive-order-13224/#state.

[xix] Phil Stewart, “U.S. Tells Türkiye it Supports Ankara’s Fight Against the PKK,” Reuters.com, May 11, 2017. https://www.reuters.com/article/us-mideast-crisis-Türkiye-mattis-idUSKBN1871F0.

[xx] Michael Radu, “The Rise and Fall of the PKK,” Orbis 45, no. 1 (2001): 47-50.

[xxi] Reuters staff (no byline), “U.S. Warns Against Turkish Action in Iraq,” Reuters.com, October 9, 2007. https://www.reuters.com/article/us-Türkiye-iraq-usa/u-s-warns-against-turkish-action-in-iraq-idUSWAT00822720071009.

[xxii] Cagaptay, “The PKK’s New Offensive,” 2004.

[xxiii] Karen Kaya, “A Different War on Terrorism: The U.S., Türkiye, and the PKK,” Small Wars Journal 2, no. 4 (2012): 1-7.

[xxiv] Sean McCormack (State Department Spokesman), “Press Statement,” U.S. Department of State, August 28, 2006. https://2001-2009.state.gov/r/pa/prs/ps/2006/71563.htm

[xxv] Arin Savran, “The Peace Process Between Türkiye and the Kurdistan Workers’ Party, 2009-2015,” Journal of Balkan and Near Eastern Studies 22, no. 6 (2020): 777-792.

[xxvi] F. Stephen Larrabee “Why Erdoğan Wants Peace with the PKK,” Foreign Affairs 27, no. 3 (2013). https://www.foreignaffairs.com/articles/Türkiye/2013-03-27/why-Erdoğan-wants-peace-pkk.

[xxvii] Mesut Yegen, “The 2011 Elections and the Kurdish Question,” Insight Türkiye 13, no. 4 (2011): 147-169.

[xxviii] Cengiz Candar, “Öcalan’s Message is Much More than a Ceasefire,” Al-Monitor, March 24, 2013. https://www.al-monitor.com/originals/2013/03/Öcalan-ceasefire-newroz-speech-farewell-to-arms.html.

[xxix] Margarita Konaev and Burak Kadercan, “Old Dogs, New Tricks: Urban Warfare in Türkiye’s War With the PKK,” War on the Rocks, January 3, 2018. https://warontherocks.com/2018/01/old-dogs-new-tricks-urban-warfare-Türkiyes-war-pkk/.

[xxx] Murat Yesiltas and Necdet Ozcelik, When Strategy Collapses: The PKK’s Urban Terrorist Campaign (Ankara: SETA, 2018).

[xxxi] Daniel Byman, “Why Be a Pawn to a State? Proxy Wars fronm a Proxy’s Perspective,” Brookings.edu, May 22, 2018. https://www.brookings.edu/articles/why-be-a-pawn-to-a-state-proxy-wars-from-a-proxys-perspective/.

[xxxii] Savran, “The Peace Process,” 777-792.

[xxxiii] Cansu Camlibel, “U.S. Relations With YPG Temporary, Transactional, Tactical,” Hurriyet Daily News, May 19, 2017. https://www.hurriyetdailynews.com/us-relations-with-ypg-temporary-transactional-tactical-113277.

[xxxiv] Ranj Alaaldin, “Türkiye, the U.S., and the YPG After the Afrin Operation?” Brookings.edu, January 26, 2018. https://www.brookings.edu/articles/whats-next-for-Türkiye-the-us-and-the-ypg-after-the-afrin-operation/.

[xxxv] Aaron Stein and Michelle Foley, “The YPG-PKK Connection,” Atlantic Council, January 26, 2016. https://www.atlanticcouncil.org/blogs/menasource/the-ypg-pkk-connection/.

[xxxvi] Michael Stephens and Aaron Stein, “The YPG: America’s New Best Friend?” Al Jazeera, June 28, 2015. https://www.aljazeera.com/opinions/2015/6/28/the-ypg-americas-new-best-friend/.

[xxxvii] Michael Knights and Lahur Talabani, “The Iraqi Kurdish Battle Against ISIS: Reports from the Front,” Washington Institute, November 6, 2015. https://www.washingtoninstitute.org/policy-analysis/iraqi-kurdish-battle-against-isis-reports-front.

[xxxviii] Christopher Blanchard, Syria and U.S. Policy, (Washington, DC: Congressional Research Service, 2023). https://crsreports.congress.gov/product/pdf/IF/IF11930.

[xxxix] Mohammed Hassan, “Why ISIS Cannot Bring the Caliphate Back to Life,” Carnegie Endowment for International Peace, July 18, 2023. https://carnegieendowment.org/sada/90221#:

[xl] Aaron Stein, Hossam Abouzahr, and Rao Komar, “Post-Conflict Stabilization: Türkiye and the End of Operation Euphrates Shield,” Atlantic Council, July 13, 2017. https://atlanticcouncil.org/blogs/syriasource/post-conflict-stabilization-Türkiye-and-the-end-of-operation-euphrates-shield/.

[xli] Edith Lederer, “Islamic State Group Still Has Thousands in Syria and Iraq and Poses Afghan Threat, UN Experts Say,” abcnews.com, August 14, 2023. https://abcnews.go.com/US/wireStory/islamic-state-group-thousands-syria-iraq-poses-afghan-102271017.

[xlii] Rich Outzen, “Prospects for U.S.-Turkish Convergence on Syria,” Atlantic Council, June 22, 2023. https://www.atlanticcouncil.org/content-series/ac-Türkiye-defense-journal/prospects-for-us-turkish-convergence-on-syria/#:~:text=

[xliii] Canan Sevgili, Azra Ceylan, Halilcan Soran, and Oben Mumcuoglu “Turkish Military Operations in Iraq and Syria,” Reuters.com, November 21, 2022. https://www.reuters.com/world/middle-east/Türkiyes-military-operations-iraq-syria-2022-11-21/.

[xliv] Rich Outzen, “Claw-Lock: An Assessment of Turkish Counter-PKK Operations in Iraq in 2022,”

Jamestown Foundation Terrorism Monitor, August 12, 2022. https://jamestown.org/program/claw-lock-an-assessment-of-turkish-counter-pkk-operations-in-northern-iraq-in-2022/.

[xlv] Daniel DePetris, “After Syrian Airstrikes, what is the U.S. End Game?” Washington Examiner, October 29, 2023. https://www.washingtonexaminer.com/opinion/after-syria-airstrikes-what-is-the-us-endgame#:~:text=

[xlvi] Office of the Secretary of Defense (OSD), “Justification for FY2024: Counter-Islamic State of Iraq and Syria (ISIS) Train and Equip Fund (CTEF),” Department of Defense, March 2023. https://www.asafm.army.mil/Portals

[xlvii] Tomas Kavalek and Miroslav Mares, “PKK’s Friends and Foes in the Middle East Since 1999,” Central European Journal of International and Security Studies 12, no. 2 (2018): 100-129.

[xlviii] Rich Outzen and Necdet Ozcelik, “US-Backed Proxy Strengthens Iranian Hand in Intra-Kurdish Struggle,” Jamestown Foundation Terrorism Monitor, May 12, 2023. https://jamestown.org/program/us-counter-terrorism-in-kurdistan-strengthening-irans-allies-at-erbils-expense/.

[xlix] Mohammed Hassan, “Deir Ez-Zor Torn Between Arab Tribes’ Struggle For Independence And The SDF’s Efforts To Subdue Them,” Middle East Institute, September 9, 2023. https://www.mei.edu/publications/deir-ez-zor-torn-between-arab-tribes-struggle-independence-and-sdfs-efforts-subdue.

[l] Sabri Sayari, “Türkiye and the Middle East in the 1990s,” Journal of Palestine Studies 26, no. 3 (1997): 44-55.

[li] Jonathan Randal, After Such Knowledge, What Forgiveness? — My Encounters with Kurdistan (Boulder, CO: Westview Press, 1999), 261-291.

[lii] Mahmut Bali Aykan, “Türkiye’s Policy in Northern Iraq 1991-1995,” Middle Eastern Studies 32, no. 4 (1996): 343-366.

[liii] Zanotti and Thomas, Türkiye, the PKK, and U.S. Involvement, 2019.

[liv] Isa Afacan, “Turkish-American Relations in the Post-Cold War Era, 1990-2005,” Ph.D. diss., (Florida International University, 2011), 84-104, 140-150. https://digitalcommons.fiu.edu/cgi/viewcontent.cgi?article=1427&context=etd.

[lv] “America Between the Turks and Kurds,” The Economist, December 13, 2006. https://www.economist.com/middle-east-and-africa/2006/12/13/america-between-the-turks-and-kurds.

[lvi] Joseph Votel and Eero Keravuori, “The By-With-Through Operational Approach,” Joint Forces Quarterly 89, no. 2 (2018): 40-47.

[lvii] Rena Netjes and Erwin van Veen Henchman, “Rebel, Democrat, Terrorist: the YPG/PYD During the Syrian Conflict,” Clingendael, April, 2021. https://www.clingendael.org/sites/default/files/2021-05/the-ypgpyd-during-the-syrian-conflict.pdf.

[lviii] Jim Garamone, “Defense Official Says Allies, Partners Are Key to Our Defense,” DefenseNews, February 10, 2023. https://www.defense.gov/News/News-Stories/Article/Article/3295507/defense-official-says-allies-partners-are-key-to-defense/.

[lix] Kathleen McInnis, “The Competitive Advantages and Risks of Alliances,” heritage.org, October 30, 2019. https://www.heritage.org/military-strength-essays/2020-essays/the-competitive-advantages-and-risks-alliances.

[lx] Steven Cook, Neither Friend nor Foe: The Future of U.S.-Turkish Relations (Washington, DC: Council on Foreign Relations Press, 2018).

[lxi] Thomas Wilkins, “’Alignment,’ not ‘alliance’ - the shifting paradigm of international security cooperation: toward a conceptual taxonomy of alignment,” Review of International Studies 38, no. 1 (2012): 53-76.

[lxii] Pavel Shlykov, “The State of Strategic Hedging: Türkiye’s Foreign Policy and Relations With Russia,” Russia in Global Affairs 21, no. 3 (2023): 134-158.

[lxiii] Rich Outzen, “Deals, Drones, and National Will: The New Era in Turkish Power Projection,” Washington Institute, July 9, 2021. https://www.washingtoninstitute.org/policy-analysis/deals-drones-and-national-will-new-era-turkish-power-projection.

[lxiv] Interviews conducted in October 2023 via written exchanges with U.S.- and Türkiye-based analysts with advanced security credentials and a minimum of two decades in security or policy analysis / practice. Names available upon request.

[lxv] Murat Yesiltas, “How Türkiye Has Changed its Counter-Terrorism Policy Against the PKK,” Politics Today, June 15, 2018.  https://politicstoday.org/how-Türkiye-has-changed-its-counter-terrorism-policy-against-the-pkk/; Yesiltas, “Making Sense of Türkiye’s New Counter-Terrorism Strategy,” Politics Today, November 23, 2018. https://politicstoday.org/making-sense-of-Türkiyes-new-counter-terrorism-strategy/.

[lxvi] Mustafa Cosar Unal and Marina Miron, “Losing a War While Defeating the Enemy: The Vitality of the Strategy Bridge,” Revista Cientifica General Jose Maria Cordova 20, no. 40 (2022): 989-1023.

[lxvii] “Türkiye’s PKK Conflict - a Visual Explainer,” International Crisis Group, September 28, 2023. https://www.crisisgroup.org/content/türkiyes-pkk-conflict-visual-explainer.

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