Turkey
Reports
The Brunson issue has become very personal for Trump and I don’t think he will back off [with Turkey] until Brunson is released.
Both the executive and legislative branches have exhausted their strategic patience [with Turkey].
Although it is unlikely the sanctions will have much practical effect in either case, it is significant and unprecedented that two NATO allies have sanctioned members of each other's government.
Trump will not back down until Brunson is home, while Erdogan does not want to look like he capitulated to the Americans.
[President Trump's tweet demanding Turkey free pastor Andrew Brunson] will complicate efforts to find a quiet diplomatic solution... Erdogan won't want to be seen as backing down in the face of U.S. pressure, but he is facing real economic challenges domestically that make him vulnerable to U.S. sanctions.
[Andrew] Brunson has really emerged as a bilateral irritant [between Turkey and the United States. His continued imprisonment by Turkey, despite personal appeals from U.S. lawmakers, is] seen as a real slap in the face to Congress... [Erdogan] has been frankly engaging in hostage diplomacy where he’s saying ‘you give me my cleric and I’ll give you yours.'