Once oriented mainly toward Europe and no more than a (wary) bystander in the Middle East and North Africa (MENA), Turkey became one of the region’s aspiring heavyweights in just over a decade. The country is bound to the neighborhood through blood and cultural ties, even if its distinct Turkish character sets it apart from the Arab world. Despite a shared history and geographical proximity that could have ensured strong commercial and diplomatic links with states formerly part of the empire, Turkey’s traditional establishment and elites long saw exposure to a conflict-ridden Middle East primarily as a liability. It was only in the 1980s that Turkey started developing closer trading, cultural, and people-to-people ties with the surrounding region. In the 1990s, after the Cold War had ended, Turkey cemented its relations with the US and Europe, and anchored its MENA regional engagement through close military cooperation with Israel.
Regardless of who led it, Turkey’s primary objective over the past century has been to retain the territory that was left to it from the wreckage of the Ottoman Empire. Ever since the 2002 elections, the country has been ruled by the Justice and Development party (AKP) under Recep Tayyip Erdoğan, first as prime minister and then as president. The AKP is a movement whose Muslim Brotherhood-inspired ideology fuses Islamic principles with participatory politics and free-market economics. AKP leaders and the conservative intellectual elites close to the government cast Turkey as a natural leader of the Islamic umma, and view the country’s borders with Iraq and Syria as an artificial imposition. At the same time, Erdoğan and his supporters have internalized the Kemalist vision of a strong state capable of deterring and overpowering internal and external enemies.
The common menace of an independent Kurdistan brought Iran and Turkey on the same track, providing both countries with a chance to coordinate and decide on how to confront the new status.
One of Turkey’s primary internal challenges – one that poses a threat to its territorial integrity and ties its fate to that of its neighbors – has been the Kurdish question. From the 1980s onward, following the creation of the Kurdistan Workers’ Party (Partiya Karkerên Kurdistanê, PKK), this has involved ferocious fighting with tenacious Kurdish separatists punctuated by deceptively peaceful lulls and even hesitant attempts at reaching across the aisle. The most recent such effort ended in July 2015; its collapse must be placed within the context of the AKP’s reduced showing in elections the previous month, and the PKK’s expanding fortunes in the gaping vacuums of Syria and Iraq. The Turkey-PKK conflict, now in its fourth decade, has been tremendously costly and damaging to all sides – especially to the civilians caught in the crossfire. It has become a festering wound for which no workable treatment has yet been found.
"Zero Problems" in the Neighborhood
Soon after coming to power in 2002, the AKP pivoted Turkish foreign policy towards its neighborhood, most distinctly, MENA. It was a decision that was particularly popular with the party’s base of conservative small-business owners, especially in Anatolia, who profited from an increase in cross-border trade and investment. The economy took off. This allowed Turkey, full of swagger, to appoint itself as the region’s order setter (düzen kurucu). That was the essence of the “zero problems” policy enunciated by Ahmet Davutoğlu, an academic who went from being Erdoğan’s foreign policy advisor to the foreign minister, and lastly to prime minister during the heady years of Turkish economic expansion. The ruling party championed a regional marketplace by forging free-trade agreements and lifting visa requirements for its neighbors. If Europe had its Schengen, Turkey was to build its “Sham-gen” (Sham is Arabic for the Levant), some argued.
Middle Eastern publics, raised on Egyptian and Syrian soap operas, now fell in thrall with (dubbed) Turkish TV series, as well as Turkish consumer goods and tourist attractions. Turkey offered something to those looking for alternatives to their own sclerotic authoritarian regimes. Arab liberals admired Ankara’s EU-induced – but broadly embraced in Turkey – political and institutional reforms as well as its overall pro-Western outlook, while Muslim Brotherhood supporters were attracted to the AKP’s reformulation of Islamism in a modern key, with economic results.
As an important component of what some referred to as “emerging neo-Ottomanism,” Ankara believed it could parlay its new popularity, economic strength, and growing regional networks into diplomatic muscle deployed in furtherance of conflict resolution. It presented itself as a mediator between Israel and Syria in 2007 (though talks became public only in May 2008) and having friendly relations with both; between Israel and Hamas; and between Iran and the UN Security Council over Tehran’s nuclear program. It no longer saw MENA conflicts as threatening, but as opportunities.
The AKP’s Brotherhood-infused ideological outlook soon created contradictions in its peacemaking efforts. In 2006, it endorsed Hamas (the Brotherhood’s Palestinian expression) after it won the elections in the West Bank and Gaza, diverging from the Quartet, which linked acceptance of the results with the Islamist movement’s recognition of the state of Israel and renunciation of violence. From that point onward, Israel no longer saw Ankara as an honest broker but as a challenger, one with the kind of soft-power influence in the region that Israel signally lacked, and one that pursued alliances, or at least workable relations, with Israel’s enemies: Hamas and Iran. Israeli-Syrian negotiations – and Turkish mediation along with it – fell apart when the Israeli army invaded Gaza in December 2008. Ankara blamed Tel Aviv for presenting it with a fait accompli. Tensions escalated, first in a January 2009 showdown between Erdoğan and President Shimon Peres at the World Economic Forum, then more dramatically in May 2010, when Israel’s attack on the “Gaza Freedom Flotilla” (sponsored by the Humanitarian Relief Foundation/İnsani Yardım Vakfı , or IHH, a Turkish NGO close to the AKP) provoked a rupture in diplomatic relations. Turkey’s mediation with regard to the Iranian nuclear program in 2010 hardly fared better, ending in failure after Washington declined to support it.
It was in Syria – where the stakes for Turkey are incomparably high – that its aspiration to refashion the MENA region suffered its most dramatic crash.
Ankara’s approach to post-2003 Iraq was wrought with contradictions and ultimately failed dismally. While its relations with the Saddam Hussein regime were never very solid, it saw a strong Iraq as a critical buffer against Iranian influence and shared Saddam’s interest in keeping the Kurds divided and weak. Ankara warned against the US invasion of Iraq, and the Turkish parliament – contrary to the wishes of Turkey’s military leadership – refused transit rights to US troops seeking to bring down the Iraqi leader via a pincer movement from Kuwait, Jordan, and Turkey. While this may not have affected the war’s outcome, it did fray Ankara’s relations with Washington and left Turkey out in the cold for five years. Worse for Turkey, the US military’s disastrous errors in stabilizing and rebuilding Iraq afforded Iran an increasingly influential role in shaping the country’s political course, and provided the Iraqi Kurds with vast new opportunities.
In a moment of clear thinking, Turkey counter-intuitively began forging a strategically important economic bond with the Kurdistan Regional Government (KRG) in 2007, particularly with its strongest component, the Kurdistan Democratic Party (KDP) of Kurdish President Masoud Barzani. Ankara’s objective was to contain the Kurdish challenge to Iraq’s territorial integrity – and ipso facto Turkey’s own – by drawing the Kurds tightly into its economy while allowing them the kind of autonomy, including the opportunity to exploit the region’s hydrocarbon wealth, that Baghdad had been averse to extending since Iraq’s birth but, after 2003, could not prevent. At the same time, the Turkish leadership overcame its distaste of Iraq’s new Shiite Islamist ruling parties and reached out to Baghdad, signing a series of commercial agreements that formed the basis for major Turkish investments in the Iraqi economy. Ankara hoped it could mediate a deal between Baghdad and Erbil that would keep the Kurds in Iraq, and both Kurdish and Kirkuk oil flowing into Turkey.
Turkey soon shot itself in the foot. In the run-up to Iraq’s 2010 parliamentary elections, Turkey, in coordination with Qatar, set about building a secular political counterweight to Prime Minister Nouri al-Maliki’s Islamist-tinged Shiite ruling alliance. But by drawing mainly Sunni parties into Iyad Allawi’s Al-Iraqiya list, Turkey compounded Iraq’s sectarian politics. When Allawi won the plurality of votes but proved unable to cobble together a governing coalition, Maliki returned to power and promptly took revenge on Allawi’s foreign sponsors, especially Turkey. Sectarian rhetoric soared in Ankara and Baghdad, and commercial ties suffered. These antecedents would come back to haunt Ankara after 2011. Since then, it has been drawn deeply into the vortex of the region’s interlocking conflicts while facing significant blowback at home.
Accumulating Challenges in a Crumbling Neighborhood
The Arab awakenings put Turkish regional policy to an ever more rigorous test. Initially, it seemed that history was on the AKP’s side, with years of investment about to pay off. Sensing commercial and political opportunity in the Arab world at a time when EU membership negotiations had reached a stalemate, Turkey presented its multiparty politics, economic vibrancy, synthesis of Islam, and democracy as a model – or, as former President Abdullah Gül put it, a “source of inspiration” – to the region. Erdoğan, who was prime minister at the time, became a hero of Tahrir Square with an early call on Hosni Mubarak to step down. First vetoing NATO’s Libya intervention from fear of losing its extensive economic investments there, Ankara then threw its weight behind the anti-Qadhafi coalition and ended up on the winning side. With the old autocrats gone, Tunisia, Egypt, and Libya all saw Brotherhood affiliates triumphing. Not only were they ideologically aligned with the AKP, but they were also the best-organized political force and were capable of assuming power. Turkey’s fortunes rose with Al-Nahda’s March 2011 electoral victory in Tunisia and Mohammed Morsi’s 2012 ascendancy to the Egyptian presidency.
Instead of Turkey changing Syria in its own image, the Syrian war transformed Turkish domestic politics and regional policy.
In Syria, Ankara expected Assad to fall in the face of growing popular protests. Then came the reversal, shattering in its impact. Assad stayed on, requiring growing Turkish investment in an insurgency that never ceased to fragment and radicalize. Turkey’s support of the Brotherhood backfired, delivering a blow to its political and commercial interests in the region: The Egyptian military, backed by Saudi Arabia, toppled Morsi in July 2013; Turkey responded by cutting diplomatic ties. In Tunisia, seeing the writing on the wall, the Al-Nahda government resigned pre-emptively, agreeing to being replaced by an interim technocrat government and subsequently to a power-sharing arrangement with secular forces. Lastly, the 2015 nuclear deal between Iran and the P5+1 diminished Turkey’s value to Tehran as a bridge to the West (as well as a way around the sanctions). As many in Turkey quipped, from zero problems with neighbors, the country now had zero neighbors without problems.
It was in Syria – where the stakes for Turkey are incomparably high – that its aspiration to refashion the MENA region suffered its most dramatic crash. In the popular uprising’s early months, Assad shunned Erdoğan and Davutoğlu’s calls for reform, resorting to harsh repression instead. This triggered a sharp Turkish U-turn in August 2011. Betting on Assad’s speedy demise, Turkey burned bridges to the regime by offering a safe haven to its opponents, a conduit for arms and foreign fighters, and a refuge for displaced civilians. The gamble backfired. A military stalemate dragged Ankara deeper into the civil war, straining its relations with Iran and Iraq. The hope that Western states would intervene and impose a no-fly zone, as they had in Libya, evaporated once President Barack Obama chose not to enforce his declared red lines on Syrian chemical weapons use in September 2013.
Things went downhill from there. Turkey now faced a triple challenge: from the PKK, whose Syrian affiliates were exploiting the vacuum in the north to carve out a self-rule entity along the length of the Turkish border; from ISIS, which emerged from the chaotic Turkey-supported Syrian rebel scene and in 2015-2016 carried out repeated attacks on Turkish soil, including in Ankara (the bloodiest in Turkey’s history) and Istanbul, taking hundreds of lives; and from 3.2 million (registered) Syrian refugees, who somehow had to be accommodated and cared for.
The dual threat from the PKK and ISIS presented a particularly knotty dilemma. In the balance of things, Ankara felt the PKK posed the greater menace, having built up a formidable guerrilla force and seeking a political transformation in, if not secession of, Turkey’s southeast. The July 2015 collapse of a Turkey-PKK ceasefire brought a sharp escalation in fighting in Kurdish cities in Turkey’s southeast, and a more aggressive Turkish military approach toward the presence of the PKK and its affiliates in Syria and Iraq. While Ankara did not align itself with ISIS, it benefited from the group’s presence in Syria, where its fighters fought the regime (but also other Syrian rebel factions) and attacked the Kurdish self-rule area. ISIS’ October 2014 seizure of the Kurdish border town of Kobane triggered a US-backed military response from the People’s Protection Units (YPG) – the PKK affiliate – over strenuous but eventually fruitless Turkish opposition: Ankara did not want to see the PKK make military gains on its southern border and accumulate Western credit in the process.
In early 2015, Turkey saw a glimmer of hope that Assad might yet fall, but Russia’s military intervention in September ended any prospect of regime change in Damascus. Worse, after the Turkish air force shot down a Russian fighter jet, the Kremlin imposed tough sanctions on Turkey, reversing what had been a stable economic relationship. The combined power of Russia, Iran, Hizbollah, and what remained of the Syrian army, pushed back hard against Turkey-backed rebels. As the YPG extended its control in the north, seeking to connect the areas east of the Euphrates with Afrin north of Aleppo, Erdoğan realized he had little choice but to reconcile with Moscow and re-engage Iran. In return, he received tacit approval to move military forces and Free Syrian Army units into Syria (Operation Euphrates Shield, launched in August 2016), ostensibly to fight ISIS but in reality to stop the YPG’s bid to take control over the entire 900-kilometer border. Together with Russia, Turkey brokered the rebels’ surrender in East Aleppo in December and sponsored several rounds of Moscow-initiated peace talks in Astana and Geneva, with Iran as co-host. A year later, Turkey’s role in Syria was much diminished. In August 2017, it agreed with Russia to establish a jointly monitored de-escalation zone in Idlib province, which had come under the near-exclusive sway of an – apparently autonomous – Al Qaeda affiliate, the Nusra Front. Ankara appeared motivated as much by the possibility of containing the PKK’s Syrian affiliate, the YPG, in Afrin as by the desire to prevent a new refugee flow into Turkey as a result of a future Syrian regime assault on Idlib.
Most of the gambles the AKP took, starting from the mid-2000s but especially from 2011 onwards, boomeranged.
In Iraq, Turkey hardly fared better. ISIS’ capture of Sunni Arab areas in June 2014, including the city of Mosul, drew Iraqi Shiite militias – some of which were funded, trained, and equipped by Iran – to northern Iraq, a traditional Turkish sphere of influence. This was the first time since the 1639 Treaty of Zuhab between the Ottoman and Persian Empires that the two sides came to face each other in this area, even if only by proxy.
To make matters worse for Turkey, the PKK made major inroads in northern Iraq as well, challenging Turkey’s ally the KDP, which pre-emptively abandoned the district of Sinjar in August 2014 as ISIS moved in. PKK fighters saved thousands of fleeing Yazidis; many others were slaughtered or enslaved by ISIS. More than a year later, the PKK and the KDP – moving simultaneously but separately – started to push ISIS out of the area, leaving the PKK (and its local affiliates) in an advantageous position, the KDP having lost the trust of the local population. During the subsequent US-led campaign to wrest control of Mosul from ISIS, Turkey played hardly more than a bystander role, having sent only a small number of troops into northern Iraq to train Sunni forces under Mosul’s former governor and deter the PKK from taking further advantage of the security vacuum. Still, this move put Ankara on a collision course with Baghdad, which decried Turkey’s violation of Iraqi sovereignty, while its support of the KDP aggravated intra-Kurdish tensions.
Ankara’s post-2008 relationship with the KDP, which had enabled the Kurdish region’s integration into the Turkish economy, suffered a severe blow as a result of President Masoud Barzani’s decision to stage an independence referendum over its strenuous objections. On the day of the September 2017 referendum, Erdoğan went so far as to warn Barzani that if the Kurds failed to “go back on this mistake as soon as possible, they will go down in history with the shame of having dragged the region into an ethnic and sectarian war.” Sanctions followed but more importantly, Ankara closed its eyes to a subsequent move by Iraqi security forces supported by Iran-backed Shiite militias to restore federal control over the disputed territories (the borderlands between majority-Kurd and majority-Arab areas in northern Iraq), including Kirkuk and its oil fields. These developments were a strategic disaster for Turkey, which saw an almost decade-long investment in a seemingly reliable Kurdish partner collapse overnight and its rival Iran improving its strategic position in Iraq.
Setbacks in Syria, Iraq, and the broader region pushed Turkey into a retrenchment mode. Instead of Turkey changing Syria in its own image, as many Turks had hoped in 2011 it would do, the Syrian war transformed Turkish domestic politics and regional policy. To prevent further isolation and maintain its position, Ankara began to repair relations with Israel, tried to restore economic ties with the Sisi regime in Egypt, reopened its embassy in Libya and even toned down its anti-Assad rhetoric, reportedly establishing a backchannel to Damascus. At the same time, Turkey has clung to its alliance with Qatar, a fellow sponsor of the Muslim Brotherhood and since 2016 host to a Turkish military base. This relationship was even strengthened during Qatar’s Gulf squabble with Saudi Arabia and the UAE that broke out in June 2017. Turkey also has remained steadfast in its backing of Hamas in Gaza. In short, Turkey has traded its comfortable “zero-problems-with-neighbors” stance for one of crisis management in a desperate effort to protect its own vital interests at home and along its borders.
Being in but not truly of the region – to use Churchill’s adage about Britain and Europe – Turkey long succeeded in living with conflicts next door without incurring inordinate costs. Presenting itself as a neutral third party, at least initially, in the Israel-Palestine conflict and Iran’s standoff with the West gave it a regional profile as peace mediator, even if some in the West saw Turkey abandoning its staunchly pro-Western alignment. Sunni radicalization in the region was a boon for the AKP early in its tenure, as it conferred legitimacy in the West’s eyes of being a “moderate Islamist” party at a time when it was locked in a life-or-death struggle with the Kemalist “deep state.”
The Arab Awakenings and their violent aftermath served to unravel the edifice that AKP leaders had built. Most of the gambles the AKP took, starting from the mid-2000s but especially from 2011 onwards, boomeranged. Turkey’s challenge today is to restore equipoise in its regional relations and in particular to prevent any further negative spillover from the conflicts and vacuum in Syria and Iraq, while finding ways to address its own worsening internal convulsions.
 See Philip Robins, Suits and Uniforms: Turkey’s Foreign Policy after the Cold War (London, 2003); William Hale, Turkish Foreign Policy Since 1774 (Abingdon, 2013), chapter 11.
 On the merger of political Islam and Turkish nationalism, including the Millî Görüş (“National Outlook”) tradition from which the AKP stems, see Jenny White, Muslim Nationalism and the New Turks (Princeton: Princeton University Press, 2014).
 See Simon Waldman and Emre Çalışkan, The New Turkey and Its Discontents (Oxford, 2016), chapter 7.
 Ahmet Davutoğlu used the term düzen kurucu bir ülke (“an order-setting country”) in his “Strategic Depth: Turkey’s International Position” [Stratejik derinlik: Türkiye'nin uluslararası konumu] (Istanbul, 2001).
 The word Sham-gen was reportedly coined by Erdoğan himself in relation to agreements Turkey signed with Syria, Iran and Iraq. It was made public by an Iranian minister, Ali Agha-Mohammadi. Milliyet, 3 March 2011. See Kemal Kirişci and Neslihan Kaptanoğlu, “The Politics of Trade and Turkish Foreign Policy,” Middle Eastern Studies, Vol. 47, No. 5 (September 2011), pp. 705-724.
 Meliha Benli Altunışık, Turkey: Arab Perspectives (Istanbul: 2010).
 On neo-Ottomanism as a foreign policy doctrine, see Ömer Taşpınar, “Turkey's Middle East Policies: Between Neo-Ottomanism and Kemalism,” Carnegie Papers, No. 10 (September 2008).
 See Waldman and Çalışkan, op. cit.; and Ibrahim Kalın, “Turkey’s foreign policy in 2011: An assessment,” in Dimitar Bechev (ed.), “What Does Turkey Think,” European Council on Foreign Relations (2011), pp. 51-57.
 Starting officially in May 2008, but in all likelihood even earlier, Syrian and Israeli officials held negotiations in Turkey, with Damascus touting prospects for a deal on regaining control over the Golan Heights. In September, Assad held a summit with French President Nicolas Sarkozy, Erdoğan, and the emir of Qatar to give a push to the peace talks. The Syrians delivered a peace plan to Israel via Turkey. At the end of 2008, Erdoğan and Israeli Prime Minister Ehud Olmert probed the idea for direct talks. BBC, 23 December 2008.
 Having been allowed by Israel to develop economic projects and channel aid to Gaza, Turkey attempted to mediate in the case of an Israeli soldier held by Hamas. In 2016 Israeli President Reuven Rivlin asked Erdoğan for help in recovering the bodies of two Israeli soldiers killed during the 2014 invasion of Gaza. Middle East Monitor, 29 November 2016.
 Turkey hosted talks between the P5+1 and Tehran, as well as between EU Foreign and Security Representative Catherine Ashton and Saeed Jalili, Iran’s chief nuclear negotiator, in 2011-2013. In 2010, Turkey had designed a solution with Brazil, a fellow non-permanent UN Security Council member, which failed to gain US approval. See Kemal Kirişci, “Is a Deal with Iran Bad for Turkey?” The National Interest, 21 January 2014.
 Turkey complained that Israel failed to give it forewarning. Interviews by Crisis Group consultant in previous capacity, senior officials. Ankara, November 2010.
 Dan Arbell, “The US-Turkey-Israel Triangle, Brookings, October 2014.
 David E. Sanger and Michael Slackman, “U.S. Is Skeptical on Iranian Deal for Nuclear Fuel,” The New York Times, 17 May 2010; and Laura Rozen, “Obama admin. dismisses leak of Obama letter on Iran fuel deal,” Politico, 28 May 2010. Turkey used its position as a non-permanent member of the UN Security Council in 2009-10.
 Bill Park, “Strategic Location, Political Dislocation: Turkey, the United States, and Northern Iraq,” Middle East Review of International Affairs, Vol. 7, No. 2 (June 2003); Waldman and Çalışkan, op. cit., chapter 7.
 Barzani had tried to reach out to Ankara for a long time, as did Turkey to the KDP starting with President Turgut Özal (1989-1993) in 1991. (Özal also engaged with Jalal Talabani’s PUK). Barzani paid six official visits to Turkey between 1991 and 2001. Åsa Lundgren, “Defending through violation: Ankara's contradictory strategies over the Turkish-Iraqi border,” in Inga Brandell, State Frontiers: Borders and Boundaries in the Middle East (London, 2006), p. 111; Bill Park, “Turkey’s policy towards Northern Iraq: problems and prospects,” Adelphi Paper No. 374 (London, 2005)
 Crisis Group Middle East and North Africa Briefing N°81, Turkey and Iraqi Kurds: Conflict or Cooperation?, 13 November 2008.
 Crisis Group Middle East and North Africa Report N°94, Iraq’s Uncertain Future: Elections and Beyond, 25 February 2010.
 Gül first used the phrase in an early interview as head of state, years before the Arab Awakenings. “US must share power in new world order, says Turkey's controversial president,” The Guardian, 15 August 2008; Soli Özel, “The AKP’s foreign policy in context,” in Bechev, What Does Turkey Think, pp. 69-75.
 Steven Cook, “Erdoğan’s Middle Eastern Victory Lap,” Foreign Affairs, 15 September 2011.
Aaron Stein, Turkey's New Foreign Policy: Davutoğlu, the AKP and the Pursuit of Regional Order (RUSI, 2014).
 In Libya, the Muslim Brotherhood lost in the July 2012 elections. As the country descended into internecine conflict in mid-2014, Turkey, acting in concert with Qatar, threw in its lot with the Brotherhood-dominated General National Assembly based in Tripoli and the so-called Government of National Salvation headed by Khalifa Ghweil, antagonising the House of Representatives, which had relocated to Tobruk, and its regional sponsors Egypt and the UAE. Barın Kalayoğlu, “Why is Turkey making a return to Libya?” Al-Monitor, 14 June 2014; Aaron Stein, “Turkey’s Proxy War in Libya,” War on the Rocks, 15 January 2015.
 Assad and Erdoğan developed a close personal relationship in the 2000s. Assad came to Ankara in 2004 (the first Syrian leader to do so since the 1940s), and Erdoğan travelled to Damascus at the end of the same year to sign a free-trade agreement. The two families even used to vacation together.
 For a comprehensive account of Turkey’s zig-zagging between March and August 2011, see Christopher Phillips, The Battle for Syria: International Rivalry in the New Middle East (Yale, 2016), chapter 3.
 Crisis Group Middle East and North Africa Briefing N°51, Turkey and Iran: Bitter Friends, Bosom Rivals, 13 December 2016.
 Crisis Group Middle East and North Africa Report N°176, The PKK’s Fateful Choice in Northern Syria, 4 May 2017.
 On 10 October 2015, ISIS bombed a rally co-organized by the pro-Kurdish Peoples’ Democracy Party (HDP), claiming the lives of 103. The earliest incident of a terrorist attack related to Syria were the twin lorry bombs exploding in the border town of Reyhanlı (Hatay) in May 2013 leaving 52 dead. No one has claimed responsibility. There are conflicting allegations linking it to either Assad’s secret services and Jabhat al-Nusra.
 “Number of Syrian refugees in Turkey reaches 3,2 million”, Daily Sabah, 4 October 2017, https://www.dailysabah.com/syrian-crisis/2017/10/04/number-of-syrian-refugees-in-turkey-reaches-32-million. See also, Crisis Group Europe and Central Asia Report N°241, Turkey’s Refugee Crisis: The Politics of Permanence, 30 November 2016.
 The PKK has its headquarters in northern Iraq’s Qandil mountain range, and has bases along the length of the Iraq-Turkey border. On the PKK’s ideology, see Crisis Group, The PKK’s Fateful Choice, pp. 3-5.
 For background on the talks’ collapse, see Crisis Group Europe Briefing N°77, A Sisyphean Task? Resuming Turkey-PKK Peace Talks, 17 December 2015.
 Turkey ultimately allowed the transfer of Kurdish peshmerga fighters from northern Iraq to Kobane. Al Jazeera, 29 October 2014. The U.S. also delivered heavy weapons through this route after Barzani and the U.S. promised Turkey they would not be passed on to the PKK or its Syrian affiliate, the YPG. Rudaw, 25 October 2014.
 Selin Girit, “Turkey faces big losses as Russian sanctions bite”, BBC News, 2 January 2016. See also Dimitar Bechev, Rival Power: Russia’s Influence in Southeast Europe (Yale, 2017), chapter 5.
 See Crisis Group, The PKK’s Fateful Choice.
 As ISIS seized Mosul, it overran the Turkish consulate, taking hostage its 49 Turkish staff, including the consul-general. They were released in late September 2014 following secret negotiations and payment of what one must assume was a significant ransom. The Guardian, 20 September 2014.
 UN Human Rights Council, “‘They came to destroy’: ISIS Crimes Against the Yazidis,” 15 June 2016, http://ohchr.org/Documents/HRBodies/HRCouncil/CoISyria/A_HRC_32_CRP.2_en.pdf.
 Wilson Fache, “What Is the Turkish Army Really Doing in Iraq?” Al-Monitor, 8 September 2016.
 Quoted in The Guardian, 26 September 2017.
 Crisis Group Middle East & North Africa Briefing N°55, Oil and Borders: How to Fix Iraq’s Kurdish Crisis, 17 October 2017.
 On Turkey-Israel, see Al-Monitor, 1 July 2016; on Turkey-Egypt, see Al-Monitor, 17 February 2017; on Turkey-Libya, see Reuters, 30 January 2017; and on the Turkey-Assad backchannel, see Foreign Policy, 12 July 2016.
 See, for example, European Stability Initiative, Islamic Calvinists. Change and Conservatism in Central Anatolia, September 2005; Angel Rabasa and F. Stephen Larabee, The Rise of Political Islam in Turkey (RAND, 2008.). At the time, Erdoğan insisted the AKP was a Turkish replica of the Christian Democrat parties in Western Europe. Ian Traynor, “Turkey strives for 21st century form of Islam”, The Guardian, 27 February 2008.