Turkish President Recep Tayyip Erdogan said Thursday that he had informed President Obama of Turkey's intent to participate in an offensive in northern Syria. His remarks are a reminder of the strategic conundrum facing the United States, which is working to defeat the extremist Islamic State in Syria and Iraq with both cooperation from Turkey as well as from Syrian Kurdish militias being targeted by the Turks.

In a televised speech from the Turkish capital, Ankara, Erdogan said he told Obama that Syrian rebels backed by Turkey in an ongoing operation called “Euphrates Shield” would advance on the Syrian border town of al-Bab, which is held by the Islamic State. They would then march on to Manbij, a northern Syrian city that earlier this year was liberated from the Islamic State by a coalition of Syrian militias led by a Kurdish faction known as the People's Protection Units, or YPG. The Turkish government considers the YPG an affiliate of the outlawed Kurdistan Workers' Party, or PKK, a Kurdish separatist faction that has waged a decades-long insurgency within Turkey and is deemed a terrorist group by both Ankara and Washington.

Then, Erdogan said, “we will go toward Raqqa” — the de facto capital of the Islamic State in Syria.

All of this comes at a time of fitful battlefield action that has Turkey feeling nervous. While the United States struggles to marshal forces to encircle and isolate Raqqa, the Iraqi government is in the second week of its offensive to reclaim the northern city of Mosul, which the Islamic State wrested away from Baghdad's control in 2014. There, a coalition of factions is also operating somewhat in tandem, including Kurdish militias loyal to Iraq's semiautonomous Kurdish regional government.

And there, too, Turkey hopes for “a place at the table.” As WorldViews noted earlier, Erdogan has demanded a role for Turkish troops in the Mosul campaign that nobody — neither the Americans, nor the Iraqis — has planned for and has invoked grievances from World War I and sectarian rhetoric while doing so.

“We did not voluntarily accept the borders of our country,” Erdogan said, referring to the defeated Ottoman parliament's disregarded 1920 territorial claim to Mosul and its oil-rich environs.

In the same vein, the Turkish leader's remarks about taking Raqqa were probably a response to recent comments by senior U.S. officials, who indicated that the YPG would have to be among the militias that take on the Islamic State in Raqqa.

“The facts are these: The only force that is capable on any near-term timeline are the Syrian Democratic Forces, of which the YPG are a significant portion,” Gen. Stephen Townsend, who is leading the coalition operation against the Islamic State, told reporters Wednesday.

That reality irks Turkey, which has been shelling YPG-controlled areas in Syria for months and appears eager to further push back the Kurdish territorial gains across swaths of northern Syria.

“If it doesn’t stop, it could preempt all plans for Raqqa,” a Pentagon official told Washington Post columnist David Ignatius this week when discussing Turkish attacks on the YPG.

Meanwhile, doubts still surround the capabilities of the Turkish-backed rebels, who may struggle to even capture al-Bab, let alone make inroads toward Manbij and Raqqa, according to intelligence analyst Rao Komar.

“Urban sieges in Syria generally require a numerically superior attacking force. With many rebels leaving northern Aleppo and returning to other parts of Syria, Euphrates Shield does not have the required manpower to easily take the city from the Islamic State,” he writes for the website War on the Rocks. “Fractures in the rebel coalition may decrease cooperation between rebel groups, which in turn hinders battlefield effectiveness.”

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