In this fourth episode, Adam Day speaks to Fanar Haddad, Senior Research Fellow at the Middle East Institute at the National University, about the battle against the Islamic State, tracing the formation of ISIS back to the Iraq War that began in 2003. They focus on the Popular Mobilization Units, paramilitary groups that sprung up in 2014 in local Iraqi communities to defend themselves against ISIS, and consider the role that the Popular Mobilization Units play in the Iraqi State today.