Turkey Blames Kurdish Militia for Ankara Attack, Challenging U.S.

BAGHDAD — In blaming a Syrian Kurdish militia supported by the United States for a deadly car bombing in Ankara, Turkey added new urgency on Thursday to a question its president recently posed to the Obama administration: Are you on the side of a NATO ally — Turkey — or its enemies?

The militia, which adamantly denies any role in the bombing, is the administration’s most important ground force inside Syria in the fight against the militants of the Islamic State. But it is also fast becoming an enemy of Turkey, which views the militia as a national security threat because of its links to another Kurdish militant group that is battling for autonomy within Turkey.