According to Western governments, more than 12,000 of their citizens have traveled to Syria to join the so-called Islamic State of Iraq and Syria (ISIS) in various capacities including frontline fighters. Estimates also show that 8,000 citizens of some 20 other nations have also traveled to ISIS-held territory to lend a helping hand.

The question is: How do they get there?

Judging by public statements from Western officials, including France’s Prime Minister Manuel Valls, the answer is that self-styled jihadists reach ISIS territory via Turkey. British Prime Minister David Cameron says his government is in contact with Turkish authorities to trace a number of London teenage girls who are suspected of having joined ISIS.

At the same time, Iraqi authorities claim that they have fired on a number of aircraft suspected of smuggling arms and materiel to ISIS. Again, the question is: What country’s airspace did the planes traverse to reach ISIS territory?

Again, the obvious answer is: Turkey.

Western intelligence sources quoted by the media suggest that ISIS is sitting on a war-chest of around 2 billion US dollars, partly stolen from banks in Iraqi and Syrian cities captured over the past 18 months and partly thanks to exports from oilfields seized in Syria and Iraq.

ISIS, reportedly offering fairly attractive salaries to its jihadists, has operational costs of around 20 million US dollars a month. At least part of this is covered by donations from abroad.

Again, the question is: How does the money get to the ISIS “capital” of Raqqa?

Here the answer is a bit more complicated.

Go to any money transfer service in London, Paris or Berlin and you will have little trouble sending cash—albeit in sums no larger than 2,000 US dollars—to any address in Syria. However, when it comes to larger transfers one quickly encounters Turkish banks, often operating through branches in Vienna and the Turkish segment of Cyprus.

Another question: How does ISIS manage to feed the population under its control and secure medical and pharmaceutical supplies needed for an estimated population of 2.8 million?

The answer once again points to Turkey in the shape of the endless line of heavy trucks crossing the border every day often under the bored gaze of Turkish frontier guards.

This is strange behavior by any standards. Turkey is a member of the North Atlantic Treaty Organization (NATO) and, theoretically at least, still an ally of the United States which is, again theoretically, leading a “coalition” to fight ISIS.

In other words while one NATO ally claims to be fighting ISIS another is enabling ISIS not only to resist but also to expand its territory.

At first glance, this doesn’t make sense.

A closer look, however, may offer pointers to a tentative explanation.

Turkish President Recep Tayyip Erdoğan is convinced that his American counterpart Barack Obama is not serious about fighting ISIS. In Erdoğan’s analysis, Obama’s strategy will lead to Iranian domination of Iraq and parts of Syria, in addition to Lebanon where Tehran is also in control through its Hezbollah agents. Worse still from Ankara’s point of view, Obama’s policy could lead to the emergence of a mini-Kurdish state on Turkey’s southern border in Syria. To counter Iran’s domination and the emergence of a Kurdish entity in Syria, Turkey needs ISIS as a balancing force. Erdoğan suspects Obama of even accepting a future role for Bashar al-Assad in Syria within the context of an overall deal with Iran. US Secretary of State John Kerry’s old friendship with the Assad clan makes such concerns more credible.

Erdoğan, who has a suspicious mind, also fears that the US is already plotting to overthrow his regime by promoting the cleric-cum-businessman Fethullah Gülen as an alternative leader in Ankara.

Gülen, who lives in the US, is in regular contact with the Obama administration which is ignoring Ankara’s demands for his extradition on largely cooked-up charges.

The savage media campaign launched against Erdoğan by Iran is fanning the flames of the Turkish leader’s suspicions about a joint Washington-Tehran plot to unseat him, particularly as Obama has publicly invited Iran to “seize the opportunity” to become the “leading power in the region.”

Erdoğan is especially sore about Obama’s refusal to take any action against the Assad clan. Ankara sees the US president’s so-called plan to train anti-Assad fighters in Turkey as an attempt at subterfuge to cover a deeper and more sinister strategy.

Thus, as far as Erdoğan is concerned, the tactical alliance between Ankara and Raqqa makes sense, at least in the short run.

Erdoğan believes that things will clear up in a couple of years’ time.

First, he hopes to win another general election this year, thus consolidating his hold on power for five more years. In that context he is engaged in dense negotiations with imprisoned Kurdish leader Abdullah Öcalan to cook up an accord to woo Kurdish voters in eastern Anatolia. Without that Kurdish vote, Erdoğan would find it hard to secure a majority in the rest of Turkey where opposition to his autocratic rule is on the rise.

Erdoğan also believes that the Rafsanjani faction in Iran, now controlling the presidency in Tehran, will be crushed in next year’s general election and thus will be unable to deliver on the fancy promises made to Washington. More importantly, Erdoğan knows that the Obama administration is on its last leg and, despite the president’s efforts to tie the hands of his successor, no future US president will pursue Washington’s current convoluted foreign policy. (Even a President Hillary Clinton would want to reverse Obama’s destructive strategy).

For all that, Erdoğan’s policy is deeply flawed. It is opportunistic and unprincipled.

Implicit support for ISIS might have made strategic sense if the self-styled ISIS “Caliph” Abu Bakr Al-Baghdadi enjoyed genuine grass-root support at least in the areas he has captured, not to mention the Arab states of the Middle East as a whole. However, the best evidence available shows that ISIS is deeply unpopular even among radical Arab Sunnis. Thus, once ISIS is crushed, as it is bound to be, Turkey might find itself on the losing side. Having lost its NATO allies, Turkey could also become isolated in its own regional habitat.

Erdoğan’s Kurdish policy is also a jumble of contradictions. He has allied himself with one faction among Iraqi Kurds, thus pushing other factions towards Iran. His hope of dividing Turkey’s own Kurds is dicey to say the least. Even if he makes a deal with the captive Öcalan, many of Turkey’s ethnic Kurds will still not forget Ankara’s ambiguous stance during the fight over Kobani.

Erdoğan criticizes Obama for refusing to see Assad and ISIS as two halves of the same problem. However, Erdoğan is making the same mistake only in reverse by acknowledging the evils of Assad but ignoring the equally evil ISIS.