It is rare that relations between two neighboring countries go through such rapid transformation from bad to good and then good to bad as those between Turkey and Syria. The worsening of relations with Syria has been accompanied by a series of problematic outcomes, including refugees, trade, and Kurdish separtists. But in the middle of tensions, Turkey has shied away from unilateral actions on Syria, insisting that the response to the challenge should be multi-lateral and within the confines of international law.