More The Syrian civil war reached a turning point last week when forces loyal to the regime of president Bashar al-Assad cut a key supply line into rebel-held city of Aleppo, imperiling one of the key strongholds of the nearly five-year-old rebellion. Further advances by the regime and allied militias could place Aleppo under siege, striking a potentially crushing blow for the insurrection that began a series of unarmed protests against Assad’s authoritarian regime in February 2011 and later metastasized into a civil conflict that left more than a quarter million Syrians dead. The Russian air force, which has supported the regime’s offensive against the rebels since October 2015, has intensified airstrikes in the Aleppo area over the last week.