Turkey’s behavior should not come as a shock to observers of the region. Ankara’s support for jihadists dates back to at least 2013, when the Turkish National Intelligence Agency established the jihadi highway from Urfa (in Turkey’s southeast) to Raqqa—then under the control of ISIS. More than 40,000 foreign fighters from about 100 countries transited through Turkey to Syria. Turkey provided weapons, money, and logistical support, as well as medical services to wounded fighters.
Turkey made little attempt to hide this support for jihadists. At Harvard University in October 2014, Vice President Joe Biden indicated: “President Erdogan told me…we let too many people through.’ Now, they’re trying to seal their border.”