The wild card in the west’s fight against Islamic State radicals is Turkey, a NATO ally whose powerful leader has a penchant for sending mixed messages on where he stands and what he’s willing to do to help stem terror-driven bloodshed in Syria and Iraq.

The White House announcement last week that Turkish President Recep Tayyip Erdogan had met with Vice President Joe Biden and agreed to allow the U.S. and its coalition partners to use Turkish air bases to launch strikes against Islamic State targets in northern Syria was seen as a diplomatic breakthough and a sign that the historically pro-western nation was on the same page as Washington.

“For him, the overarching goal is the overthrow of Assad, not stopping Islamic State.”

- Lehigh University Professor Henri Barkey

Two days later, in a speech to the Organization of Islamic Cooperation in Istanbul, Erdogan demonstrated jarring contempt for the west.

“I speak clearly,” Erdogan told the gathering. “Those who come from outside [the Muslim world] only like the oil, gold, diamonds, cheap workforce, conflicts and disputes of the lands of Islam. Believe me, they do not like us. They like seeing us, our children die. How long we will continue to tolerate this?”

The comments came on the heels of another Erdogan claim that Muslims discovered America, a claim that drew more ridicule than diplomatic analysis.

The conflicting postures came as Kurds, long enemies of Erdogan’s democratically-elected, yet increasingly Islamic government, accused Turkey of allowing Islamic State suicide attacks on the besieged northern Syrian city of Kobani to be launched from within its borders.

"We are 100-percent certain that the ISIS suicide vehicle entered Kobani through Turkey," said Kurdish leader Asya Abdullah, claiming the Kurdish People's Protection Units (YPG) had all other approaches sealed off.

 Those charges followed longstanding claims that Ankara has allowed a flood of international jihadists to pour into Syria and Iraq via Istanbul. Also, in April photographs appeared online of ISIS commander Abu Muhammad receiving treatment in a hospital bed in Turkey and in May, PYG forces attacked an ISIS-controlled village and allegedly seized documents attesting to ISIS militants' presence in Turkey.

Erdogan’s own rhetoric is little help in determining if the links between his nation and the Islamic State militants are genuine, or simply the product of local sympathies and a border that defies official control.

Lehigh University Professor Henri Barkey, an expert on Turkey, said the ambiguity emanating from Ankara is nothing new in the complex relationship between the U.S. and Turkey, which has long sought to use its standing as an Arab power and its ties to the west to make it an important player on the world stage.

Erdogan's musings

Turkish President Recip Tayyip Erdogan has made several statement of late that have prompted outrage, ridicule or simply head-scratching around the world. Here are some of his more memorable and controversial remarks:

-  "You cannot place a mother breastfeeding her baby on an equal footing with men."

- "You cannot get women to do every kind of work men can do, as in Communist regimes. You cannot tell them to go out and dig the soil. This is against their delicate nature.”

- “The child who took down the [Turkish] flag, will pay the price. I don’t care if that was a child!"

- "Is the Nobel awarded objectively? No. Does the UN Security Council make objective decisions? No, never." 

-  "Recently, very strangely, ambassadors get involved in some provocative acts. I am calling on them: Do your job, if you leave your area of jurisdiction we do not have to keep you in our country."

- "They [International actors, not including the Turkish government] are making Sykes-Picot agreements hiding behind freedom of press, a war of independence or jihad."

- "Muslims discovered America in 1178, not Christopher Columbus."

“The Turkish-American relationship is exceedingly deep and not one that can be upended easily,” said Barkey, of the Pennsylvania school’s international relations department. “But the Turks have never been easy allies. The joke has always been that you ask them for something, they say ‘No,’ and then negotiations begin.”

Erdogan’s position is complicated by his well-chronicled dislike of embattled Syrian President Bashar al-Assad. Three years ago, Assad looked like he would be the latest casualty of the Arab Spring and the vacuum in Damascus would be filled by the Erdogan-aligned Muslim Brotherhood. But the U.S. commitment to ousting Assad has taken a back seat to stopping Islamic State, as the radical army’ size and territory has swelled.

“We are not supporting an overthrow of Assad, and that is what he is upset about,” Barkey said. “For him, the overarching goal is the overthrow of Assad, not stopping Islamic State.”

In addition to allowing the use of its bases, Turkey has pledged to train 2,000 opposition forces to counter extremism in the region.  While the Kurds will likely never believe Erdogan’s commitment to fighting ISIS, the U.S. and its allies have little choice but to hope he means what he tells them.

“Can he be trusted?” Barkey asked rhetorically. “Erdogan is increasingly erratic, and he has his own agenda and it is not ours.

“But we should not exaggerate the differences between Turkey and the U.S., in the sense that there is a certain inertia that governs the relationship that makes it work,” he said, adding that much of what Erdogan says is posturing to both his domestic constituency and to the Sunni Arab world, of which he sees himself a leader.

“There has never in modern history been a single Turkish leader who has come out and said to the Turkish public, ‘We are allies of the U.S. because we share common values and goals,” Barkey said. “You can’t be seen to be pro-U.S. inside of Turkey.”

Biden, after meeting with Erdogan and Turkish Prime Minister Ahmet Davutoglu last week, seemed to acknowledge the difficult diplomatic dance between the two nations.

The two nations have “always [been] direct with one another,” Biden said, adding that they have “tackled a number of very contentious issues, regionally and internationally, and we’ve always eventually come out on the same side.”

Emily Casswell is a freelance journalist based in Istanbul