From Freedom Fighters to Jihadists: Human Resources of Non-State Armed GroupsAt the start of the Syrian conflict in 2011, thousands of pro democracy rebel groups spontaneously formed to fight the Assad regime. Years later, the revolution was unrecognizable as rebel opposition forces had merged into three major groups: Jabhat al Nusra, Ahrar al Sham, and the Islamic State in Iraq and Syria (ISIS). Why did these three groups rapidly increase in size and military strength while others simply disappeared? What is it about their