Jassim Mohamad, writer and policy analyst
Turkey has become a central platform for Islamist groups in the region, and the government, led by President Recep Tayyip Erdogan, has been repeatedly criticized for its handling of these issues. In particular, European and Arab states have repeatedly criticized Ankara’s lax attitude to jihadists transiting its territory on their way to Syria. The Turkish opposition has published details about Turkey’s dealings with the Islamic State (ISIS). And the Turkish government’s policies towards other Islamists have provoked controversy from the Gulf to Egypt about interventions in the internal affairs of other states.
Jihadists Crossing Turkey
The Independent newspaper in Britain reported in early 2018 that ISIS fighters were hiding in Turkey after the collapse of the “caliphate” and some were preparing to enter Europe to carry out terror attacks. European governments have urged Turkey prevent ISIS fighters crossing into Syria and vice versa, but so far the results have been limited.
An ISIS member named Ebdulhemit Dimeshk, who went from Morocco to Turkey before crossing into Syria, was captured by the Kurdish-controlled Syrian Democratic Forces (SDF), a group Turkey views as a terrorist organization. From SDF custody, Dimeshk is reported to have said: “I don’t know what kind of agreement Turkey and the [Islamic] State have, but they let me through very comfortably. I did cross through official channels”.
The Balkan states neighboring Turkey complained bitterly at earlier points in the war about the lax border controls, which were causing problems for their security. Around the same time, The Guardian reported that as ISIS spread in northern Syria it ran a sophisticated border-control operation, with Turkey as the main gateway for foreign fighters.
There have been numerous reports of ISIS fighters receiving medical treatment and other logistical support inside Turkey. The Russian government has claimed it has proof of business deals between Turkey and ISIS on oil, albeit that the crossings Moscow claimed were being used were in fact held by anti-ISIS forces. Another ISIS emir in SDF custody, Razeek Radeek Maksimo, claimed oil had been sold by ISIS both to Turkey and to the Russians’ client regime in Syria. 
The scale of the traffic across the border made it seem unlikely the Turkish government was unaware of what was happening.
Abdullah Bozkurt, a prominent opponent of the Erdogan government, a member of the Gulen movement, claims that “hundreds of secret wiretap records obtained from confidential sources in … Ankara reveal how … Erdogan has enabled—and even facilitated—the movement of foreign and Turkish militants across the Turkish border into Syria to fight alongside jihadists in [ISIS].” 
More recently, after Turkey’s Operation Euphrates Shield pushed ISIS away from the border, the Turks have claimed that they can finish off the ISIS remnants in eastern Syria. As Steven Cook of the Council on Foreign Relations has pointed out, this is very unlikely: Turkey will continue prioritizing the Kurdish threat, the SDF, rather than ISIS.
ISIS Weapons Made in Turkey
A recurring accusation is that ISIS’s materiel — weapons, explosives, drones, and generators — were acquired from Turkey.
For example, ISIS’s generator of choice is the iSTA Breeze i-500, which, according to its website, are “100% made in Turkey, manufactured by Altinel Enerji LTD. in Istanbul”.
A Turkish newspaper, Hurriyet, reported, at a time when it was run by the Gülenist opposition to Erdogan, that ISIS possessed explosives that were of the same standard as a state, namely Turkey, and that much of the raw material, from sugar to aluminum to cement, came from facilities in Turkey.
French sugar group Tereos says that 45 tons of French-produced sorbitol, an artificial sweetener that can be used to make rocket propellants, vanished in Turkey in 2015 and resurfaced in the hands of ISIS.
Imams Spying for Turkey
Turkey’s policy of monitoring the diaspora in Europe has frequently brought it into conflict with European states, not only because of the basic issues around espionage but on more principled matters like free expression, where the European and Turkish understandings of what is legitimate and what is not do not align.
An investigation by Der Spiegel in 2017 confirmed that Erdogan’s government was using the Turkish-Islamic Union for Religious Affairs (DITIB) as a means to spy on the Turkish population in Germany and identify opponents, particularly Gülenists, believed by Ankara to be behind the coup attempt. DITIB has become associated in the popular mind in Germany with Turkish spying operations, and last year the Bavarian regional government indicated that it no longer excludes DITIB from supervision by the domestic intelligence agencies.
Turkey has been accused of much more serious interference in the internal affairs of Libya and Egypt. Ahmed al-Mismari, a spokesman for General Haftar’s Libyan National Army, said in April 2019 that Turkey was shipping weapons to terrorist groups in his country, even after promises that such things would stop. And a military analyst in Egypt claimed that Turkey trying to create a base for ISIS in Libya and the Sinai.
The Turkish government’s record is one of applying insufficient pressure against ISIS and other jihadist groups that try to use its territory, either for transit or as a base for planning operations further afield. With the collapse of ISIS’s “caliphate”, and the movement of jihadists to Sinai, Afghanistan, and Europe, it is vital that this challenge be addressed, and that Ankara is not permitted to manipulate the situation to its own advantage. Erdogan did not hesitate to threaten to open the borders to Europe if his demands were not met. Europe should likewise respond with strong measures to put an end to this threat to national and international security.
 Turkey accused of recruiting ex-Isis fighters in their thousands to attack Kurds in Syria https://www.independent.co.uk/news/world/middle-east/turkey-isis-afrin-syria-kurds-free-syrian-army-jihadi-video-fighters-recruits-a8199166.html
 All ISIS roads lead to Turkey https://anfenglishmobile.com/features/all-isis-roads-lead-to-turkey-33402
 Balkans Track ISIS Fighters Flowing Through Turkey, Overwhelmed By Lax Border Control By Erin Banco https://www.ibtimes.com/balkans-track-isis-fighters-flowing-through-turkey-overwhelmed-lax-border-control-1980602
 Exclusive: Passenger manifests seized by Kurdish forces at Tel Abyad have same stamp marks as other Isis documents the Guardian has been able to verify https://www.theguardian.com/world/2016/jan/10/isis-immigration-operation-turkey-syria-border-passenger-manifests-tel-abyad-islamic-state
 Is Turkey collaborating with the Islamic State (ISIS)? https://docs.house.gov/meetings/FA/FA14/20170405/105842/HHRG-115-FA14-Wstate-PhillipsD-20170405-SD001.pdf
 Russia releases video of Daesh tankers in Turkey https://www.youtube.com/watch?v=Hef942-ZXKo
 Russia says it has proof Turkey involved in Islamic State oil trade https://www.reuters.com/article/us-mideast-crisis-russia-turkey/russia-says-it-has-proof-turkey-involved-in-islamic-state-oil-trade-idUSKBN0TL19S20151202
 Turkey’s Support of Terrorists in Syria Exposed in Secret Wiretaps https://armenianweekly.com/2019/02/12/turkeys-support-of-terrorists-in-syria-exposed-in-secret-wiretaps/
 Turkey Is Lying About Fighting ISIS, By Steven A. Cook, https://foreignpolicy.com/2018/12/28/turkey-is-lying-about-fighting-isis/
 Powering Islamic State — an open-source analysis of Turkish-made generators used by Daesh, Benjamin Strick, 3 July 2018, https://medium.com/@benjamindbrown/powering-islamic-state-turkish-company-wind-generators-a07ff269124b
 The ISIS Rockets “Made In Turkey” https://www.worldcrunch.com/the-endless-war-1/the-isis-rockets-made-in-turkey
 French company says rocket propellant supply sold to Turkey now with ISIS https://ahvalnews.com/islamic-state/french-company-says-rocket-propellant-supply-sold-turkey-now-isis
 Turkey’s Worldwide Monitoring of Suspected Gülen Supporters https://www.spiegel.de/international/europe/turkey-spies-on-suspected-guelen-supporters-around-the-world-a-1141367.html
 Sky News Arabia – Al-Mismari accuses Turkey of supporting militias in Libya
 Youm7 – Khaled Okasha: Turkey Supports Militias in Syria to Block a Political Solution.