Kurds diverting fight from ISIS to defend against Turkish attacks

U.S. loses key ally in its effort to track down the last pockets of militants

WASHINGTON — The U.S.-led campaign to hunt down the last pockets of Islamic State militants in Syria has lost its most effective battleground partner in what U.S. military officials fear will stall a critical phase of the offensive and leave open the door for hundreds of foreign fighters to escape.

Thousands of Kurdish fighters and commanders who make up the backbone of the Syrian Democratic Forces in recent weeks have diverted to defend Afrin, in Syria’s northwest, where other Kurdish militias are facing sharp attacks from Turkish troops.

The Kurdish-led SDF was the driving force last fall in routing the Islamic State group from its self-proclaimed headquarters in Raqqa and chasing insurgents fleeing south along the Euphrates River Valley to the Iraqi border. That fight now is largely reliant on Syrian Arab fighters who make up a majority of the SDF but lack the Kurds’ military organization and logistical prowess.

In congressional testimony Tuesday, Gen. Joseph L. Votel, head of U.S. Central Command, described the SDF as “the most effective force on the ground in Syria against ISIS,” using an alternative name for the Islamic State.

“And we need them to finish this — to finish this fight,” Votel told the House Armed Services Committee.

Without the Kurds, the Arab forces and their U.S. military advisers have largely been forced to halt clearing operations and taken up mostly defensive positions, U.S. officials said. That has left U.S. air power to pick up the slack.

The development is another major consequence of the fighting that has rapidly unfurled in recent weeks in Syria’s tumultuous northwest.

It threatens not only to slow progress against several hundred Islamic State fighters who are hiding along the Euphrates River or in nearby deserts, but also could allow battlehardened foreign fighters to escape deeper into western Syria and eventually into Turkey or Jordan — and possibly to return home to Europe or Africa to commit mayhem there, U.S. commanders and analysts said.

Thousands of foreign fighters have already fled unfettered to the south and west through Syrian army lines, these officials said.

Mauricio Lima / New York Times Zinareen Anas, a commander of the Womens Protection Forces, a Kurdish militia receiving U.S. help, pushed Islamic State forces out of Ain Issa, Syria.