A coalition of US-backed Syria rebels and Islamist groups like Ahrar al-Sham have come together in a plan to attack the key ISIS city of Jarabulus, on the western short of the Euphrates River. Unlike most offensives, this one will be cross-border, being launched from inside Turkey.
The rebel force includes substantial numbers of fighters who heretofore had been defending the key border town of Azaz. With ISIS recently focusing more on defense, they’ve decided to go after Jarabulus, another valuable border crossing. With a lot of ISIS territory between Azaz and Jarabulus, however, they decided it was simpler to go through Turkey, and Turkey was apparently fine with the idea.
Turkey’s interest in this is that the Kurdish Syrian Democratic Forces (SDF) recently took the city of Manbij, with major US backing, and that’s making Jarabulus tougher for ISIS to defend. Turkey has long warned that the Kurds taking Jarabulus was a “red line” for them.
Instead of risking a US-backed push into Jarabulus, Turkey seems to be hoping this faction, dominated by Ahrar al-Sham, will get there first, precluding any more Kurdish advances across the Euphrates River into key border areas.