There's a lot riding on Aleppo. The battle for the Syrian city of enormous strategic and geographic importance will determine who holds political leverage in negotiations for the country's future.
Meanwhile, another battle is taking place that could significantly affect the fight for Aleppo. To the city's north, in the border town of Jarablus, Turkey is fighting its first direct battle in Syria against the Islamic State — though the objective of this military campaign is not to defeat IS as much as it is to prevent Kurdish militias from creating an autonomous area in Syria that could foster Kurdish separatism within Turkey itself.