WASHINGTON — Even as it prods Turkey to step up in the global fight against Islamic State militants, the United States is worried that Ankara might use military action to target Kurdish fighters who are the last line of defense against extremists trying to take over the Syrian border town of Kobani.
In a careful-what-you-wish-for scenario, U.S. officials acknowledge that drawing Ankara into the war could open a new line of attack against a Kurdish movement that has for decades sought greater autonomy inside Turkey.
At the same time, Americans officials fear Turkey could simply choose to remain out of the fray, and let two of its enemies — the Islamic State group and Kurdish guerrillas— fight for Kobani. That would give the militants an opportunity to do as much damage to the Kurdish fighters in Syria as possible.
Neither scenario is agreeable, the officials said. The issues and implications are expected to be broached — delicately — when U.S. envoys coordinating the international response to the Islamic State group meet on Thursday and Friday with Turkish leaders in Ankara. The officials spoke on condition of anonymity because they were not authorized to discuss the diplomatic situation by name.
For months, Turkey resisted using force against the Islamic State, which has rampaged through large amounts of territory just over its borders in Iraq and Syria. Until recently, its reluctance had been mostly excused out of security concerns for dozens of Turkish diplomats and employees who were kidnapped by the militants from the Iraqi city Mosul in June. The hostages were freed last month.
Since then, American officials have grown increasingly frustrated by Ankara's inaction against the Islamic militants, yet simultaneously nervous about what a Turkish military response would mean for the Kurdish fighters at Kobani.
Secretary of State John Kerry and Turkish Prime Minister Ahmet Davutoglu have spoken at least twice this week, and special U.S. envoy retired Marine Gen. John Allen is hoping for answers in his meetings in Ankara on how Turkey plans to join the battle.
"Clearly, on their border, this is of enormous concern to Turkey — and they recognize that," said Kerry, who also described the U.S. as "deeply concerned about the people of Kobani."
Kerry also sounded a note of caution. "These things have to be done in a thoughtful and careful way so everybody understands who is doing what and what the implications are of their doing it and where you go as a result," he said Wednesday.
Last week, Turkey's parliament approved a measure to allow for assaulting the Islamic State group, a step the U.S. and other world leaders viewed as Ankara's decision to enter the conflict. But largely left unsaid was that the measure still allows Turkish troops to take aim at the Kurdish separatists. The Kurdish fighters in Syria, known as the YPG, are tied to the Kurdistan Worker's Party, or PKK, the Kurdish separatist guerrilla movement that is fiercely opposed by the Turks. Both Ankara and Washington have designated the PKK as a terrorist organization.
Ankara is "committed to fighting ISIS terrorists and PKK terrorists," said Bulent Aliriza, a former Turkish diplomat now at the Center for Strategic and International Studies in Washington, using an acronym for the Islamic State militants.
Turkey "has not intervened in Kobani to break the siege," Aliriza said. "The question is, if it were to intervene, would it fight both?"
The PKK and Turkey agreed to a cease-fire last year, but the relative peace has begun to unravel. Tensions between the two sides have flared frequently, and this week alone, 14 people were killed as Kurdish protesters clashed with police in Turkey over Ankara's hands-off approach in Kobani.
The U.S. does not consider the Syrian Kurdish fighting force or its political wing, the Kurdish Democratic Union, terrorist organizations. Still, Washington has distanced itself from both. The State Department said this week that U.S. officials have engaged with the Kurdish political party only through intermediaries.
But the Obama administration knows that the Kurdish fighters in Syria are the only force on the ground standing between the Islamic State militants and Kobani. More than 400 people have been killed in brutal clashes, according to activists, and fighting has forced at least 200,000 town residents and villagers to flee across the border into Turkey.
Days of airstrikes by the U.S. and coalition forces helped the Kurdish fighters push back the Islamic State extremists on Wednesday, a day after the militants appeared poised to take over the town.
Even so, "Kobani could be taken. We recognize that," Pentagon spokesman Rear Adm. John Kirby said Wednesday in Washington. "Air power is not going to be alone enough to save that city."
Turkey has said it does not want Kobani to fall. The country boasts the second-largest army among NATO forces, and has stationed a handful of troops in Syria — at a memorial south of Kobani that is dedicated to Suleyman Shah, grandfather of Osman I, founder of the Ottoman Empire.
Ankara has long called on the U.S. to increase its own military action in Syria — both against Sunni extremist groups and the government of President Bashar Assad. For years, Turkish President Recep Tayyip Erdogan has demanded the creation of a humanitarian corridor buffer zone inside Syria, as well as a no-fly zone to secure Turkey's borders and stem the flow of refugees.
The White House and Pentagon maintained Wednesday that the U.S. is not considering supporting a buffer zone in Syria, which would be costly, complex and controversial to enforce.
But Kerry and British Foreign Minister Philip Hammond both said the idea of a buffer zone was worth examining, although they stopped short of endorsing it. Their comments came after French President Francois Hollande spoke with Erdogan and issued a statement in Paris announcing his support for a buffer zone to protect refugees.