Weeks after Turkish forces started to deploy in large numbers to the border with the Syrian province of Idlib, Ankara appears to be on the verge of launching yet another significant military operation into Syria. Unlike Operation Euphrates Shield, which targeted lands occupied by the Islamic State, the upcoming operation into Idlib will be directed toward lands occupied by Syrian rebels. As befitting a convoluted conflict such as Syria, Turkey's advance into Idlib will be assisted by other Syrian rebel groups trained over time by Turkey in neighboring Aleppo province, and according to Turkish President Recep Tayyip Erdogan's latest indications, will be supported by Russian aviation....