It’s no secret that Turkey has become the weak link in the fight against the Islamic State (ISIS). Recep Tayyip Erdoğan, Turkey’s Islamist president, sees the world through an ethnic and sectarian chauvinist lens, and simply cannot conceive the Islamic State as a greater threat than Syria’s secular Kurds, his conspiratorial vision of Israel and Jews, or Syrian President Bashar al-Assad and Syria’s Alawis.

Turkey has provided medical aid, safe haven, and perhaps even weaponry to the Islamic State. But its biggest contribution has been free passage. A huge preponderance of the foreign fighters flowing into Syria and Iraq have transited Turkey. It’s as easy as flying in on Turkish Air, transferring to a domestic flight to Gazientep or Hatay near the Syrian border, and then paying a taxi driver to go to the border. Turkish border guards at most charge a $40 bribe to turn the other way, according to journalists and analysts who have made the journey.

I spent much of the last week in Morocco for the Marrakech Security Forum, where I had the opportunity to speak to Arab security professionals. Issues relating to foreign fighters dominated conversations. For example, why is it that so many Moroccans fight for the Islamic State inside Syria and Iraq and yet are poorly represented in Boko Haram’s emirate or in Libya, where the Islamic State is also resurgent? Or, conversely, since Islamist radicalism is rife in Algeria, why is it that Algerians are relatively poorly represented in the Islamic State, but yet are ever present in the Libyan fight?

Sometimes, the answers are mundane. It comes down to the Turkish visa regimen. Turkey does not require visas for Moroccans, making Syria accessible to would-be Moroccan jihadists. Ditto for Libyans, Lebanese, Jordanians, and Tunisians. And yet, Turkey requires visas for Algerians, hence the relatively small number of Algerians fighting in Syria and Iraq. It’s simply much easier for Algerians to fight in Libya which has proximity in its favor.

Meanwhile, Moroccans have reported a shift over time in how their extremists travel to fight in self-conceived jihads. In the past, Islamist enablers would recruit young Moroccans and help facilitate their travel to the world’s hotspots. Today, however, most of the Moroccans traveling to join the Islamic State understand they need only fly to Istanbul and then they will easily find a facilitator inside Turkey. Whether in Istanbul’s airports or in regional cities, Islamic state spotters find young would-be jihadis exiting the airport and make themselves known. Picture pimps at the Port Authority bus terminal in New York approaching girls coming off buses from the Midwest in the 1970s; when you’re trained to spot the young and naive, it’s relatively easy work.

This raises two simple policy fixes which might cut off some of the oxygen from the Islamic State:

• First, if Turkey is serious about the fight against terrorism, it needs to start requiring visas in advance from nationalities which today serve as the chief recruiting pool for the Islamic State. Businessmen and legitimate tourists won’t have a problem applying, and Turkish intelligence might benefit from the vetting as well.
• And, second, if would-be Islamic State fighters have no problem finding Islamic State fixers in and around Turkey’s airports, then it’s curious that the Turkish intelligence service can’t identify and round them up. Here, the problem is likely less ability than desire on the part of the Turkish government. But that’s no reason to deflect diplomatic attention to a real problem. Once again, perhaps it’s time to designate Turkey a state sponsor of terrorism if only to pressure the Erdoğan government to do what a responsible member of the international community would have done years ago.