Turkey considers the Kurds a terrorist insurgency, but they’ve been the most reliable partner for the U.S. in fighting the Islamic State in a strategic part of northern Syria.

The details: Mr. Trump’s decision, which goes against the recommendations of top officials in the Pentagon and the State Department, would involve pulling back the 100 to 150 U.S. troops who are deployed to the area.

Background: President Recep Tayyip Erdogan of Turkey has demanded a “safe zone” along the Turkish-Syrian border that would be used for the involuntary return of at least a million Syrian refugees.

Another whistle-blower emerges

An intelligence official with “firsthand knowledge” has provided information related to President Trump’s dealings with Ukraine, lawyers representing the official said on Sunday.