Rebel forces opposing President Bashar al-Assad – mainly composed of Hayat Tahrir al-Sham (HTS) and allied factions – have launched their biggest offensive in years this week, controlling a majority of Syria's second city of Aleppo according to a monitor. The apparent success of HTS's surprise operation rest primarily on "popular discontent", said Marc Pierini, former EU ambassador to Syria and Turkey, adding that the Assad regime has failed to restore the lives of citizens since taking control in 2016.